cylinder

r =  d/2  =   6/2  = 3

SA  = 2pi r  ( r  + h)  =  2pi * 3   ( 3 + 8)   =  66 pi  in^2  ≈   207.345 in^2

Hey there!

The rule for the suface area of a cylinder is:

$SA=2\pi r^2+dh$

Knowing this we can just plug the numbers into this:

$SA=(2\times \pi \times 3^2)+(6\times 8)=...inches^2$

Let me know how you go :)