triangular prism has 2 equilateral triangular faces as bases and 3 lateral rectangle faces.
the dimensions are as follows
equilateral triangle - sides - 4 inches each
height - 3.5 inches
area of 1 equilateral triangle - 1/2 x side x height
= 1/2 x 4 inches x 3.5 inches
= 7 sq.inches
As the base is an equilateral triangle, all 3 sides of the triangle are equal, hence, all the rectangles have the same breadth and height
rectangle - length - 5 inches
breadth - 4 inches
area of 1 rectangle = length x breadth
= 5 x 4 = 20 sq.inches
lateral area - area of the rectangle faces
= 20 x 3 rectangle faces
= 60 sq.inches
total surface area = base area + lateral area
= (area of triangles x2) + 60
= (7x2) + 60
total surface area = 74 sq.inches
