Answer:
So first, there is an acronym for the strategy, KFC.
°π°
Keep the first fraction. Ex, 4/5 ÷ 1/5
Flip the second fraction. Ex, 4/5 ÷ 5/1
Change symbol. Ex, 4/5 ÷ 5/1 turns into 4/5<em>x</em>5/1
I'm assuming the function is f(x) = 100(0.7)^x. This is the same as y = 100(0.7)^x because y = f(x).
Plug in x = 0 to get
y = 100(0.7)^x
y = 100(0.7)^0
y = 100(1)
y = 100
So (x,y) = (0,100) is one point on this function curve
Plug in x = 2 to get
y = 100(0.7)^x
y = 100(0.7)^2
y = 100(0.49)
y = 49
So (x,y) = (2,49) is another point on this curve
In summary, the two points on this function curve are (0,100) and (2,49)
<em>x</em> ^2 + <em>y</em> ^2 = 9 => <em>y</em> = <em>y(x)</em> = ± √(9 - <em>x</em> ^2)
Each cross section would be a square with side length equal to the vertical distance between the upper and lower semicircles defined by <em>y(x)</em>, which is
√(9 - <em>x</em> ^2) - (- √(9 - <em>x</em> ^2)) = 2 √(9 - <em>x</em> ^2)
The area of each square section is the square of this length,
(2 √(9 - <em>x</em> ^2)) = 4 (9 - <em>x</em> ^2) = 36 - 4<em>x</em> ^2
We get the whole solid for -3 ≤ <em>x</em> ≤ 3, so integrating gives a volume of

It would be 1 inch and 15 degree arc due to the act that the radius is half.