Answer:
Step-by-step explanation:
Jack's method is equivalent because of the "law of commutative property", which means that multiplication problems have the same result no matter the order.
2x5 is the same as 5x2
The way to get the equation for the radius (r) is to get r by itself. So divide each side by 4pi
500/4pi=r^2
Now take the square root of each side to get the equation of r.
sqrt(500/4pi)=r
You need the formula: feet per second = feet/second
Now you have to recast the formula to:
feet per second * second = feet , because you want to know the number of feet.
At the bottom is the answer.
At last you have to insert the values:
28 feet per second * 20 seconds = 560 feet
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