If Bob pitched in $11 and david pitched in $4what per cent would david get..?

on friday there were 15 birds

the answer is:

the correct option is the option b.

to calculate the surface area of the right cylinder, we need to use the following formula:

from the picture we know that:

so, substituting and calculting we have:

hence, we have that the correct option is the option b.

have a nice day!