Answer:
25
Step-by-step explanation:
5 boys: 4 girls = x boys: 20 girls
Multiple of 5 to get from 4 girls to 20 girls
use the same multiple for boys
5 boys x 5 = 25
For this case we have by definition, that the total surface area of a regular pyramid with a square base is given by:

Where:
p: It is the perimeter of the base
S: It's the inclination
It is the area of the base
Substituting:

ANswer:
Option B