A student releases a marble from the top of a ramp. The marble increases
speed while on the ramp then continues across the floor. The marble travels a
total of 160cm in 4.60s.
What was the marble's final speed?
cm/s
HELP PLEASE

Answers

Answer 1

Answer:

Vf = 69.56 cm/s

Explanation:

In order to find the final speed of the ramp, we will use the equations of motion. First we use second equation of motion to find out the acceleration of marble:

s = Vi t + (1/2)at²

where,

s = distance traveled = 160 cm

Vi = Initial Speed = 0 cm/s (since, marble starts from rest)

t = time interval = 4.6 s

a = acceleration = ?

Therefore,

160 cm = (0 cm/s)(4.6 s) + (1/2)(a)(4.6 s)²

a = (320 cm)/(4.6 s)²

a = 15.12 cm/s²

Now, we use first equation of motion:

Vf = Vi + at

Vf = 0 cm/s + (15.12 cm/s²)(4.6 s)

Vf = 69.56 cm/s


Related Questions

How do very small objects behave?
a. like particles
b. like waves
c. like both waves and particles
d. like neither waves nor particles

Answers

A. very small objects behave like like particles.

Answer:

A) PARTICLES

Explanation:

VERY SMALL OBJECTS ARE BEHAVE LIKE A PARTICLES.

HOPE IT HELP.....❤❤

The_____is the division of the atmosphere where the lapse rate decreases with altitude.

Answers

Answer:

Troposphere

Explanation:

The troposphere happens to be the lowest region amongst the atmosphere. It has a length that extends from the surface to a height of about 6–10 km. And that is the lower boundary of the stratosphere among the layers of the atmosphere

The troposphere in itself is bonded on the top by a layer of air tropopause. This layer is the one which separates the troposphere from the stratosphere, and on bottom by the surface of the Earth.

You are standing on a street corner with your friend. You then travel 14.0 m due west across the street and into your apartment building. You travel in the elevator 22.0 m upward to your floor, walk 12.0 m north to the door of your apartment, and then walk 6.0 m due east to your balcony that overlooks the street. Your friend is standing where you left her. how far are you from your friend?

Answers

Answer:

The answer is "26.3 m".

Explanation:

The positive value from the x-axis is to the direction east side

The negative value from the x-axis is to the direction west side

The positive value from the y-axis is to the direction upwards side

The negative value from the y-axis is to the direction down words side

The positive value from the z-axis is to the direction southside

The negative value from the z-axis is to the direction north side

If the value is i, j, and k are the unit of the given vectors, which can be defined as follows:

[tex]\hat i, \hat -i, \hat j, \hat -j, \hat k, \hat -k[/tex]

The displacements values:

[tex]\underset{d_1}{\rightarrow} = -14 \ \hat i\\\\\underset{d_2}{\rightarrow} = 22\ \hat j\\\\\underset{d_3}{\rightarrow} = -12 \ \hat k\\\\\underset{d_4}{\rightarrow} = 6 \ \hat i\\\\[/tex]

calculating the final displacement that is  [tex]\underset{d_5}{\rightarrow}[/tex]:

[tex]\Rightarrow \underset{d_1}{\rightarrow}+\underset{d_2}{\rightarrow}+\underset{d_3}{\rightarrow}+\underset{d_4}{\rightarrow}+\underset{d_5}{\rightarrow} =0\\\\\Rightarrow \underset{d_5}{\rightarrow} \ \ = -(\underset{d_1}{\rightarrow}+\underset{d_2}{\rightarrow}+\underset{d_3}{\rightarrow}+\underset{d_4}{\rightarrow})[/tex]

         [tex]=- (-14 \hat i+ 22 \hat j -12 \hat k+ 6 \hat i)\\\\=- (-8 \hat i+ 22 \hat j -12 \hat k)\\\\=8 \hat i- 22 \hat j +12 \hat k\\[/tex]

[tex]|\underset{d_5}{\rightarrow}|=\sqrt{8^2 +(- 22)^2 +(12)^2 }\\\\[/tex]

       [tex]= \sqrt{64 + 484 +144 }\\\\= \sqrt{208 + 484}\\\\= \sqrt{692}\\\\= 26.3 \ m[/tex]

An object travels 7.5 m/s toward the west . Under the influence of a constant net force of 5.2 kN, it comes to rest in 3.2 s. What is its mass?

Answers

Answer:

m = 2218.67 kg

Explanation:

It is given that,

Initial velocity, u = 7.5 m/s

Final speed of an object, v = 0 (at rest)

Force, F = 5.2 kN

Time, t = 3.2 s

We need to find the mass of the object. Force acting on an object is given by :

F = ma

m is mass, a is acceleration

[tex]F=\dfrac{m(v-u)}{t}\\\\m=\dfrac{Ft}{v-u}\\\\m=\dfrac{5.2\times 10^3\times 3.2}{0-7.5}\\\\m=2218.67\ kg[/tex]

So, the mass of the object is 2218.67 kg

The force is always equal to the product of mass and acceleration. The mass of the object is 2218.7 Kg.

An object travels 7.5 m/s toward the west.

Under the influence of a constant net force of 5.2 kN, it comes to rest in 3.2 s.

Now,

The initial velocity of the object is 7.5 m/s.

The final velocity of the object is 0 m/s.

The object comes to the rest position in 3.2 seconds.

The formula for finding the acceleration of the object is mentioned below:

[tex]v=u+at\\0=7.5+a \times 3.2\\a= -2.34375\;\rm m/s^2[/tex]

The formula for finding the force is mentioned below:

[tex]F=ma\\-5.2 \times 10^3=m \times 2.34375\\m=2218.7 \ \;kg[/tex]

Hence, the mass of the object is 2218.7 Kg.

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QUESTIONS
An ant walks eastward for 11.1 cm, then northward for 4,4 cm and finally westward for 11.1 cm. What is the magnitude of the displacement in cm Do
not include the units in your answer.

Answers

Answer:

4.4.

Explanation:

Hello,

In this considering the attached picture, we can see that the eastward movement is represented from O to A, the northward displacement from A to B and the westward displacement from B to C, which means that the resulting displacement is marked from O to C which includes the northwards movement since eastward and westward movement are the same.

In such a way, the magnitude of the displacement is simply 4.4 cm as no other dimension is taken into account due to the return to the same initial's x-axis position.

Regards-

unit of speed is derived unit..why??

Answers

Answer:

[tex] \boxed{ \sf{see \: below}}[/tex]

Explanation:

The unit of speed is metre per second or m / s. It clearly depends on two fundamental units ; unit of length ( metre ) and unit of time ( second ). Hence , m/s is a derived unit.

Hope I helped!

Best regards! :D

The unit of speed is m/s. The two terms metre and second are fundamental quantities.

As,m/s is derived from these two fundamental quantities. Therefore, Unit of speed is a derived unit.

Why do you think the temperature does not change much during a phase change? If possible, discuss your answer with your classmates and teacher.

Answers

Answer:

Explanation:

The fact is that there exists no temperature change until a phase change is complete. That is to say, during a phase change, the energy that will be supplied is used only to separate the molecules. There is no part of it is used to increase the kinetic energy of the molecules. So its temperature will not rise, not really, since the kinetic energy of the molecules remains the same. Also, it should be noted that the average kinetic energy of the molecules does not change at the moment that melting occurs, thus the temperature of the molecules does not change.

If an object accelerates at 40 m/s^2 in four minutes ("careful this is in minutes),
what will be the final velocity? (assume the object started from rest) *

Answers

Change in speed = (acceleration) x (time)

4 minutes = 240 seconds

Change in speed = (40 m/s²) x (240 seconds)

Change in speed = 9,600 m/s

What you're actually describing here is a car pulling 4 G's for 4 minutes, and ending up going 21,475 miles per hour.

The driver would definitely NOT get a speeding ticket, because nobody could catch him.

Also, his car would heat up and shoot flames from atmospheric friction.

(He could avoid this with some fancy steering, leave the atmosphere, and end up in low-Earth-orbit.)

Actually, I hope there's nobody in the car.  His experience wouldn't be pretty.

A girl is standing in front of a magic mirror. She finds the image of her head bigger the middle portion of her body of the same size and that of the legs smaller. The order of combinations for the magic mirror from the top is

Answers

The order from the magic mirror from the top would be more larger than the bottom.

A parking lot is going to be 60 m wide and 240 m long. what dimensions could be used for a scale model of the lot?​

Answers

Answer:

it is A  or 20x80 cm

Explanation: DID IT ON APEX

WOO

The meter was originally defined so that the period of a meter-long simple pendulum would be exactly 2.00 second. (Was your measured value close to this?) Given the relationship, T^2 alpha L (T^2 is proportional to L) what would be the length of a simple pendulum, in centimeters, with a period of exactly one second?

Answers

Explanation:

Given that,

Initial length of simple pendulum, [tex]L_1=1\ m[/tex]

Initial time period, [tex]T_1=2\ s[/tex]

We need to find the length of the simple pendulum when the period is exactly 1 second.

[tex]T_2=1\ s[/tex]

We know that the time period of simple pendulum is given by :

[tex]T=2\pi \sqrt{\dfrac{L}{g}} \\\\T\propto \sqrt{L} \\\\\dfrac{T_1}{T_2}=\dfrac{L_1}{L_2}[/tex]

Put all values and find L₂

[tex]\dfrac{T_1}{T_2}=\sqrt{\dfrac{L_1}{L_2}}\\\\L_2=\dfrac{T_2^2L_1}{T_1^2}\\\\L_2=\dfrac{1^2\times 100\ cm}{2^2\ s}\\\\L_2=25\ cm[/tex]

So, the length of the pendulum with a period of exactly one second is 25 cm.

Which is developed during the process of technology design

Answers

Answer:

solution

Explanation:

A(n) __________ is developed during the process of technological design.

To find Earth's equatorial rotation speed, we should divide the circumference of Earth by a 24 hours (1 day). To find the rotation speed at any other latitude, you need the following fact: The radial distance from Earth's axis at any latitude is equal to the equatorial radius times the cosine of the latitude. (Hint: When using the cosine (cos) function, be sure your calculator is set to recognize angles in degree mode, not in radian or gradient mode.) The radius of Earth is 6380 kilometers. Vi = 1370 km/hr
Find the rotation speed for a person at latitude 35°N.

Answers

Answer:

The  value  is  [tex]v = 1370 km /hr [/tex]

Explanation:

From the question we are told that  

   The  radius of the Earth is  [tex]R = 6380 \ km[/tex]

   The  latitude is   [tex]35^o N[/tex]

Generally the Earth's equatorial rotation speed is mathematically represented as

      [tex]v_e = \frac{C}{t}[/tex]

Here  C is the circumference which is mathematically represented as

            [tex]C = 2 * \pi * R [/tex]

=>           [tex]C = 2 * 3.142 * 6380 [/tex]

=>           [tex]C = 40091.92 [/tex]

           t is the time which is mathematically represented as

           t =  24 h

So

          [tex]v_e = \frac{40091.92}{24}[/tex]        

=>      [tex]v_e = 1670.5 \ km/h[/tex]    

Generally the rotation speed for a person at latitude 35°N. is mathematically represented as

          [tex]v = v_e cos (35)[/tex]

=>       [tex]v = 1368 [/tex]

=> [tex] v \approx 1370 km/hr [/tex]

Olivia is rolling down a hill on a skateboard and is accelerating at 2.4 m/s2. After 3 seconds, she runs into Reid at the bottom of the hill. If her initial velocity was 1.5 m/s, what was her velocity when she hit Reid?

Answers

did you ever get the answer?

Answer:

8.7

Explanation:

A=2.4m/s2                        1.5m/s + (2.4m/s2)(3s)

Vi=1.5m/s                               1.5m/s + 7.2

Vf=?                                           Vf= 8.7m/s

T=3s

How is speed shown on a distance-time graph?

as the x value at the beginning of the line
as the x value at the end of the line
as the length of the line
as the slope of the line

Answers

I know this one is 10

Answer:

Divide the change in distance by the change in time.

Explanation: Divide the difference in y-coordinates by the difference in x-coordinates (rise/run or slope).

To my best knowledge It's D

A psychologist has to obtain a medical degree to diagnose and treat people with disorders.
Please select the best answer from the choices provided
T
F

Answers

Answer:

False

Explanation:

A psychologist is a person who deals with normal and abnormal mental states, emotional, and social processes and behavior of an individual in relation to one another and to their environments.

Individuals with a master's degree in psychology can work as industrial-organizational psychologists

A psychologist is not required to obtain a medical degree to diagnose and treat people with disorders.

So, the given statement is false.

Answer:

false

Explanation:

A beam of light has a wavelength of 620 nm in vacuum.
a. What is the speed of this light in a liquid whose index of refraction at this wavelength is 1.56? (Use 3.00×108 m/s for the speed of light in a vacuum.)
b. What is the wavelength of these waves in the liquid?

Answers

Explanation:

It is given that,

Wavelength of a beam of light in vacuum, [tex]\lambda_o=620\ nm[/tex]

(a) Let v is the speed of light in a liquid whose index of refraction at this wavelength is 1.56.

We know that,

Refractive index,

[tex]n=\dfrac{c}{v}\\\\v=\dfrac{c}{n}\\\\v=\dfrac{3\times 10^8}{1.56}\\\\v=1.92\times 10^8\ m/s[/tex]

(b) The wavelength of light in material,

[tex]\lambda=\dfrac{\lambda_o}{n}[/tex]

Let [tex]\lambda_1[/tex] is the wavelength of these waves in the liquid. So,

[tex]\lambda_1=\dfrac{\lambda_o}{n}\\\\\lambda_1=\dfrac{620\times 10^{-9}}{1.56}\\\\\lambda_1=3.97\times 10^{-7}\ m[/tex]

Hence, this is the required solution.


Helppppppppppppppppppppppppppp

Answers

Answer:

Car 2 is travelling in a much higher speed than Car 1.But they are travelling or meeting in the same acceleration

What is the difference between a molecule ard
a compound ?

Answers

A molecule is the general term used to describe any atoms that are connected by chemical bonds. Every combination of atoms is a molecule. A compound is a molecule made of atoms from different elements. All compounds are molecules, but not all molecules are compounds

A wooden cube of side 5cm float in water 2.0cm of its depth below the water surface and its sides are vertical calculate the density of the wood in gcm^-3. ( Density of water= 1gcm^-3)​

Answers

Answer:

The density of the wooden cube is   [tex]\delta= 0.4 \, \frac{g}{cm^3}[/tex]

Explanation:

Recall that the weight of the entire piece of wood that is floating must equal the weight of the displaced water in the case we have an object under flotation.

At the same time. we have a relationship between Volume (V), Weight (w) and density [tex](\delta)[/tex]  given by the formula:

[tex]w=\delta\,*\,V[/tex]

Since both weights must be the same, we can write the following equation:

[tex]w_{wood} = w_{water}\\\delta *\,(5\,\,cm)^3= (\frac{1\,g}{cm^3} )\,(2\,*5^2) cm^3\\\delta= \frac{2}{5} \, \frac{g}{cm^3} \\\delta= 0.4 \, \frac{g}{cm^3}[/tex]

How do you know if a boy like you?

Answers

Answer:

They cherish you

Explanation:

Answer:

They might mess with you. If you catch them looking at you they will look away quickly.

Explanation:

The table shows chronological events in the life of our Sun, a medium-sized star. Place the missing events into the correct rows of the table.

Answers

Hello, I don't see a table, but I am guessing that you are referring to the one I attached (below).

Answer:

So, the correct order of events sorted chronologically is:

1. A nebula located in the Milky Way galaxy begins pulling nearby hydrogen atoms in its orbit.

2. The Nebula shrinks in its volume due to gravity, becoming denser and hotter. But, it's not hot enough for nuclear fusion.

3. The temperature in the core of the Nebula reaches 14 million Kelvin.

4. Hydrogen atoms begin shedding their electrons and colliding with one another.

5. The Sun enters the main sequence stage. The energy created as a result of its radiation begins nurturing life on planet such as Earth.

6. The Sun uses up all the hydrogen in its core.

7. The Sun expands greatly and cools. It is larger and redder.

8. The Sun completely runs out of hydrogen to fuse. Its outer layers are pushed away, and a cloud of ionized gas surrounds its core.

9. The Sun is a white dwarf with a dim glow.

Hope this helps!

A ball is tossed up into the air with an initial speed of 5.0. How long does it take to return to the person's hand

Answers

Answer:

Explanation:

[tex]y(t) = 5t-5t^2[/tex]

When y(t) = 0, the ball is on the hand.

[tex]0=5t-5t^2\\0=5t(1-t)\\t=0,1[/tex]

It takes 1 second.

There are several different possibilities.

==>  If the 5.0 means 5 miles per hour, that's 2.24 meters per second, up.

The acceleration of gravity is 9.8 m/s down, so the ball stops, turns around, and starts falling in (2.24/9.8) = 0.229 second.  Then, after is starts to fall, it takes the same amount of time to the person's hand.

Total time = 0.457 second.

==>  If the 5.0 means 5 meters per second, up . . .

The acceleration of gravity is 9.8 m/s down, so the ball stops, turns around, and starts falling in (5.0/9.8) = 0.51 second.  Then, after is starts to fall, it takes the same amount of time to the person's hand.

Total time = 1.02 second.

==>  If the 5.0 means 5 km/minute, that's about 83.33 meters per second, up.

The acceleration of gravity is 9.8 m/s down, so the ball stops, turns around, and starts falling in (83.33/9.8) = 8.503 seconds.  Then, after is starts to fall, it takes the same amount of time to the person's hand.

Total time = 17.01 seconds.

==>  If the 5.0 means 5 furlongs per fortnight, that's about 0.00083 meters per second, up.

The acceleration of gravity is 9.8 m/s down, so the ball stops, turns around, and starts falling in (0.00083/9.8) = 0.000085 second.  Then, after is starts to fall, it takes the same amount of time to the person's hand.

Total time = 0.00017 second.

This is why all of your numbers always need their units.


A car moves in a straight line at a speed of 55.4 km/h.
How long (in seconds) will it take the car to move 1.21 km at this speed?

Answers

55.4 km => 1hr (60 min) (60×60=120 sec)

1 km => 120 ÷ 55.4

1.21 km => (120 ÷ 55.4) × 1.21

= 2.6209 sec ( 5sf )

= 2.62 sec ( 3sf )

i hope you are able to understand my solution :))

Given the displacement vector D = (2î − 6ĵ) m, find the displacement vector (in m) R so that D + R = −5Dĵ.

Answers

Answer:

R = (-2î − 6ĵ + 10k^)m

Explanation:

We are given;

D = (2î − 6ĵ)

Now, we want to find R such that,

D + R = −5Dĵ

Plugging in (2î − 6ĵ) for D in the R equation gives;

(2î − 6ĵ) + R = -5(2î − 6ĵ)j

(2î − 6ĵ) + R = -10k + 0

This is because in vector multiplication, i × j = k and j × j = 0

Thus;

(2î − 6ĵ) + R = -10k

Making R the subject gives;

R = -2î − 6ĵ + 10k^

Thus, the displacement vector R is;

R = (-2î − 6ĵ + 10k^)m

How much can having a lighted candle increase the temperature inside the shelter?

Answers

a lighted candle produces heat however not as much heat as a heater or the sun would.

A lighted candle can increase the temperature inside a shelter by a few degrees Celsius.

A lighted candle produces heat by burning fuel. The heat from the candle is transferred to the air in the shelter by conduction, convection, and radiation. Conduction is the transfer of heat through direct contact. Convection is the transfer of heat through the movement of fluids. Radiation is the transfer of heat through electromagnetic waves.

The amount of heat that is transferred to the air in the shelter depends on the size of the candle, the number of candles, and the insulation of the shelter. The larger the candle, the more heat it will produce. The more candles, the more heat will be produced. The more insulation the shelter has, the less heat will be lost to the outside. In general, a lighted candle can increase the temperature inside a shelter by a few degrees Celsius.

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Describe how excavations are done.

Answers

Answer:

It includes earthwork, trenching, wall shafts, tunneling and underground

Explanation:

which statement describes a characteristics of a question that can be answered through scientific inquiry?

Answers

Answer: it is constructed in such a way that possible answers can be tested

Explanation:

The statement that describes a characteristic of a question that can be answered through scientific inquiry is it can be answered through making observations. The correct option is B.

What is scientific inquiry?

The goal of scientific inquiry is to establish answers for this phenomenon by a continuous and creative process of questioning, observing and inferring, experimentation, collecting and organising data, finding evidence, drawing conclusions, and repeating the experiment numerous times.

The following phrases define scientific inquiry:

Asking and responding to questions is the process of scientific research.Investigative work and data gathering are part of scientific inquiry.Similar procedures and techniques are used in a scientific investigation.

Therefore, the correct option is B. It can be answered by making observations.

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The question is incomplete. Your most probably complete question is given below:

A. It can be answered by gathering opinions.

B. It can be answered through making observations

C. It must be asked by a person who is a working scientist.

D. It must have a simple “yes or “no” answer

009 10.0 points
A typical radio wave has a period of 1.5 microsecond
Express this period in seconds.
Answer in units of s.

Answers

1.5 microseconds means . . .

-- 1.5 millionths of a second

-- 1.5 x 10⁻⁶ second

-- 0.0000015 second

The Moon's center is 3.9x10 m from Earth's center. The Moon is 1.5x10^8 km from the Sun's center. If the mass of the Moon is 7.3x10^22 kg, find the ratio of the gravitational forces exerted by Earth and the Sun on the Moon

Answers

Explanation:

It is given that The Moon's center is 3.9x10⁸ m from Earth's center. The moon 1.5x10⁸ km from the Sun's center. We need to find the ratio of the gravitational forces exerted by Earth and the Sun on the Moon.

The gravitational force is given by :

[tex]F=\dfrac{Gm_em_m}{r^2}[/tex]

It means [tex]F\propto \dfrac{1}{r^2}[/tex]

So,

[tex]\dfrac{F_1}{F_2}=\dfrac{r_2}{r_1}[/tex]

r₁ = 3.9x10⁸ km

r₂= 1.5x10⁸ km

So,

[tex]\dfrac{F_1}{F_2}=\dfrac{1.5\times 10^8}{3.9\times 10^8}\\\\\dfrac{F_1}{F_2}=\dfrac{5}{13}[/tex]

Hence, the ratio of the gravitational forces exerted by Earth and the Sun on the Moon is 5:13.

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Fill in the blank to make the equation true: []+37=15 -5(4x-2) = -2(3+6x)what is the answer and how do you get it Calculate the mass in grams of 8.35 1022 molecules of CBr4. Students in a science class placed ice cubes in a cup. They were studying variables that affected how long it takes theice to melt. Select the variable that would most likely NOT affect the time it takes the ice to melt. An athlete's heart beats an average of 150 times per minute while running. How many times does the athlete's heart beat during a 26-mile race if the athlete runs at a pace of 5 minutes per mile? Katie is absent today is that a observation or inference? Which Compatibility Modes setting is available for Photoshop? NEED HELP ASAP MARK YOU BRAINLIEST what is 30+35+30= 4x + 1 + x = -4Can anybody help me solve this ? A toy car that is 0.5 ft long is used to model the actions of an actual car thatis 15 ft long. Which ratio shows the relationship between the sizes of themodel and the actual car? I NEED THIS ASAP!!! Select the statements that are false. Psychology helps you relate to people. Psychology is a study of the mind. Psychology is focused on understanding animals. Psychology is not useful as a Christian. Psychology can help you better understand others. what is the difference between genetic and other causes of health conditions Draw structures for compounds that meet the following descriptions in proton NMR:a) C2H6O; one singletb) C3H7Cl; one doublet and one septetc) C4H8Cl2O; two tripletsd) C4H8O2; one singlet, one triplet, and one quartet Which word contains a suffix?rereadunravelwatermelonentertainment URGENT!!! Pls HELPWhen dividing fractions that are represented in same terms, their quotient is simply the quotient of their numerators. Write an equation that demonstrates this. Select the sentence that uses correct parallel construction.A. The student body president would organize pep rallies and getting better food in the cafeteria.B. Sheila visited Paris last summer and climbed the Eiffel tower.C. Keith wanted to go out and buy some groceries and also filled gas in his car.D. The new high school principal came from another school in the district and is friendly.E. I like to go shopping, go trekking, and ride my bicycle. Which of the following is depicted in the image above? a. Coffins showing victims of the black death. b. Dead people laying in a pile while devils and angels carry their souls to hell or heaven.c. Wealthy young people listening to music under orange trees. d. all of the above a medical transcriptionist has a four drawer cabinet. one drawer is 4/5 full and one is 1/2 full and one drawer is 3/4 full. can the contents be combined into 3 drawers why or why not what is the most effective way to study? 85g=kg?Unit conversion.