we know that
[total surface area]= [surface area of the base]+[surface area of triangle sides]
[surface area of the base]= 4*4=16 ft²
[surface area of one triangle side] = (base*height)/2 = 4*5/2------> 10 ft²
[surface area of four triangle sides]=4*10----------> 40 ft²
[total surface area]=16+40-------> 56 ft²
the answer is 56 ft²
