Find the surface area of this prism and explain how and final exams tomorrow

Surface area formula of a prism is:
S.A = 2 × Area of base + Perimeter of base × Height of prism
So the given are:
5 cm, 2 cm, and 3 cm

The base is an equilateral triangle
So the base is 3 cm and height is 2 cm
and we know the area of a triangle is:
A = 
P = add all sides together

Substitute them:
S.A =  2 × (3)(2) + (3 + 3 + 3) × 5
       = 6 + 45
       = 51 cm²

I’ll you if you answer my questions!