Answer:
For the regular pyramid shown in picture:
Using Pythagorean theorem: L = sqrt((4/2)^2 + 11^2)
Lateral area = Area of one lateral face x 4 = (L x 4/2) x 4 = 89.4
The surface area = Lateral are + base = 89.4 + 4 x 4 = 105.4
Hope this helps!
:)
