Answer:
The answer is 3.75 or 3 3/4
SA = 2bA (base area) + LA (lateral area)
bA = r^2*pi = 13^2pi = 169pi cm^2
LA = 2r*pi*h = 2*13*pi*88,4 = 2298,4pi cm^2
SA = (2*169pi)+2298,4 pi = 338pi+2298,4pi = 2636,4pi
I'm afraid it's not 11 (unless you can round the result up, but there is no mention about it).
8 + 13 + 11 + 9 + 13 = 54
54 / 5 = 10,8
Firstly you sum all the numbers and then you divide the result by the amount of the summed up numbers.
0.04 is 1/10 of 0.4
0.4 x 0.10 = 0.04
hope this helps