Answer:
125in
Step-by-step explanation:
Each triangular face has a base of 5 in and a height of 10 in. The area of it is given by the formula ...
  A = (1/2)bh
  A = (1/2)(5 in)(10 in) = 25 in²
The square base has an area given by the formula ...
  A = s² . . . . . where s is the side length
  A = (5 in)² = 25 in²
The total area is the sum of the areas of the 4 faces and the base:
  total area = 4 × (area of 1 face) + (area of base)
  total area = 4 × (25 in²) + 25 in²
  total area = 125 in²