Answer:
B. 140π units²
Step-by-step explanation:
Surface area of a cylinder:
2πrh + 2πr²
2π(5)(9) + 2π(5²)
90π + 50π
140π
Looks like you have most of the details already, but you're missing one crucial piece.
is parameterized by

for
and
, and a normal vector to this surface is

with norm

So the integral of
is

Answer: 12
Step-by-step explanation:
106.80/8.90 =12