Given that,
An expression : 
To find,
The value of the above expression when e = 12 and f = 1/2
Solution,
We have,

Put e = 12 and f = 1/2
So,

So, the value of the above expression is 1.
Percentage change is 100% increase.
Step-by-step explanation:
- Step 1: Find volume of cylinder A using equation, V(A) = πr²h, where r = 7 in and h = 5 in
⇒ V(A) = π × 7 × 7 × 5 = 245π
and V(B) = 490π
- Step 2: Calculate percentage change from V(A) to V(B)
⇒ % change = [V(B) - V(A)/V(A)] × 100 = (490π - 245π/245π) × 100
= 245π/245π × 100 = 100% increase
The answer is B. 386 r1
Hope this helps! : )