Could someone pls help me and explain this if you know it!!

Answer:

Mary purchased 160 pounds of sand

Step-by-step explanation:

$72÷$0.45=160

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Given :

The half-life of carbon 14 is 5,730 years.

To Find :

How much would be left of an original 50- gram sample after 2, 292 years.

Solution :

We know, rate law for first order reaction is given by :

[tex][A] = [A_o]e^{-kt}[/tex]   ...1)

Here, [tex]A_o[/tex] is initial amount and [tex]A[/tex] is final amount.

And [tex]k = \dfrac{ln\ 2}{t_{0.5}}[/tex]

Putting value of half time in above equation, we get :

[tex]k = \dfrac{ln\ 2}{5730}\\\\k = 1.21\times10^{-4} \ /s[/tex]

Putting value of k in equation 1) , we get :

[tex][A] = 50\times e^{-1.21\times 10^{-4}\times 2292} = 37.89\ gm\\\\[/tex]

Hence, this is the required solution.

Answer: i have zero clue lol

Answer:

x² + y² = 841

Step-by-step explanation:

Midpoint of diameter is a center of a circle.

Coordinates of midpoint are

( [tex]x_{1}[/tex] , [tex]y_{1}[/tex] )

( [tex]x_{2}[/tex] , [tex]y_{2}[/tex] )

( [tex]\frac{x_{1} +x_{2} }{2}[/tex] , [tex]\frac{y_{1} +y_{2} }{2}[/tex] )

d = [tex]\sqrt{(x_{2} -x_{1})^2 +(y_{2} -y_{1})^2 }[/tex]

Equation of a circle with center at (h, k) and radius "r" is (x - h)² + (y - k)² = r²

~~~~~~~~~~

C(20, 21)

D(- 20, 21)

( [tex]\frac{-20+20}{2}[/tex] , [tex]\frac{-21+21}{2}[/tex] ) = (0, 0)

d = [tex]\sqrt{(-20-20)^2 +(21+21)^2}[/tex] = √3364 = 58

r = [tex]\frac{d}{2}[/tex] = 29

x² + y² = 29²

x² + y² = 841

Answer:

Step-by-step explanation:

0.25

Answer:4

Step-by-step explanation:

Answer:

Solution in photo

Step-by-step explanation:

Answer:

12 units

Step-by-step explanation:

h=2x-6

18=2x-6

24=2x

12=x

Step-by-step explanation:

[tex] - 4( - 6 + 2) [/tex]

[tex] - 4( - 4) = + 16[/tex]

Answer: A)-16

Step-by-step explanation:

Answer:

24 inches

Step-by-step explanation:

2 x 12 = 24

Answer:

29568

Step-by-step explanation:

Given that:

Length of road = 2 miles

Number of people who can fit in a area of 5 feet by 5 feet = 14

To find:

Number of people that can fit in the road of the given dimensions.

Solution:

Given that one side 2 miles wide and 5 feet deep.

First of all, we need to find number of 5 feet by 5 feet block that can be made in the given dimensions.

2 miles = 10560 feet

Number of blocks = [tex]\frac{10560}{5}[/tex] = 2112

Number of persons that can fit in one block = 14

Number of persons that can fit in 2112 blocks = 14 [tex]\times[/tex] 2112 = 29568

Therefore, the answer is: 29568

Answer: D. 2

Step-by-step explanation:

-3t + 6 = 0

1. Subtract 6 from each side

-3t + 6 - 6 = 0 - 6

-3t = -6

2. Divide each side by -3 to isolate t and get the answer to the equation

-3t/-3 = -6/-3

t = 2

You can check your answer by plugging your calculated value back into the equation and evaluating to find that 0 = 0.

Answer:

Bro? wheres the question ?

Answer:

Number B

Step-by-step explanation:

9514 1404 393

Answer:

Step-by-step explanation:

The number with the exponent is 1+0.023/4 = 1.00575. This number is greater than 1, so represents growth.

When x increases by 1, the multiplier of 800 increases by ...

  1.00575^4 ≈ 1.023199 = 1 + 2.3199%

Rounded to the nearest tenth percent, this is a 2.3% growth rate.

_____

Additional comment

The formula corresponds to a financial formula in which a 2.3% annual interest rate is compounded 4 times per year. The effective annual interest rate is almost 2.32% per year. The difference is there, but is too small to see when the interest rate is rounded to a tenth percent.

Answer:

Im pretty sure the answer is y=375x+73

Im not really sure

Answer:

m= 1/3

Step-by-step explanation:

Answer:

open comment

please mark me brilliant

Answer:

650÷26 I think hope this help

Question

a) What is the decay factor?

b) What is the percent decrease?

c) Estimate the number of black and white TV's  sold in 1999.

Answer:

a. Decay factor = 0.85

b. Percent decrease = 15%

c. 19.363  million TVs were sold

Step-by-step explanation:

Given

[tex]n = 26.8(0.85)^t[/tex]

Solving (a): The decay factor

An exponential function has the form

[tex]y = ab^x[/tex]

Where b is:

[tex]b = decay\ factor\ or\ growth\ factor[/tex]

By comparison:

[tex]b = 0.85[/tex]

Solving (b): Percentage decrease:

Percentage decrease P is calculated as follows:

[tex]P = 1 - b[/tex]

Substitute 0.85 for b

[tex]P = 1 - 0.85[/tex]

[tex]P = 0.15[/tex]

Convert to percentage

[tex]P = 0.15*100\%[/tex]

[tex]P = 15\%[/tex]

Solving (c): TVs sold in 1999

First, we need to determine the value of t for 1999

In 1997, t= 0

In 1998, t= 1

In 1999, t= 2

So, we substitute 2 for t in: [tex]n = 26.8(0.85)^t[/tex]

[tex]n = 26.8(0.85)^2[/tex]

[tex]n = 26.8*0.7225[/tex]

[tex]n = 19.363[/tex]

Answer:

Angle 6 is 47°

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

(✓x)^5

(x^1/2)^5

x^5/2

Answer:

y= -4

Step-by-step explanation:

Since x=1, then you would plug in 1 for x. 3 times 1 is 3, then you subtract 7 to get -4.

Answer:

The answer is

[tex]y = 2x + 4[/tex]

Step-by-step explanation:

Remember ↷

[tex]Slope = \frac{rise}{run} [/tex]

x = 3

I solved for x cause I wasn't exactly sure what you wanted.

Answer:

See below.

Step-by-step explanation:

The domain is the x values involved in the equation/graph. The lines seemingly goes from -5 to 6. The x values between those points also count since there is a line. Therefore, the domain of f is [-5, 6]. The brackets are used since the dots on -5 and 6 are shaded in meaning they also count for the domain.

Interval Notation: [-5, 6]

Inequality Notation: -5 ≤ x ≤ 6

9514 1404 393

Answer:

Step-by-step explanation:

The hash marks indicate that the lower triangle is isosceles. That means its base angles are equal. The external angle marked 40° will be the sum of those two equal angles, so ...

  x + x = 40°

  x = 20°.

x is one of the two acute angles in the right triangle. The other is y, which is the complement of x.

  y = 90° -x = 90° -20°

  y = 70°

_____

Additional comments

The angle marked 40° is one of a "linear pair". The other angle in that pair is the obtuse angle in the lower triangle. Its measure is 180°-40° = 140°. The two base angles of that isosceles triangle are both x°, so you have ...

  x° +x°+140° = 180°

  2x° = 180° -140° = 40°

That is, the sum of the two angles will be equal to the external angle marked 40°. The relevant theorem says "an exterior angle is equal to the sum of the remote interior angles." Remembering this is a useful shortcut, so you don't have to find the third interior angle, which is 140° in this case.