I think that answer would be C
Surface area of the pyramid= 4*(area of the triangle) + area of the square
Area of the triangle = (1/2)*base*height=(1/2)*5*5= 25/2 in²
Area of the square = 5*5 =25 in²
Surface area of the pyramid = 4*(25/2) + 25=2*25 + 25=75 in²
1/12 is the square root of 1/144
