Explanation: you are trying to find the surface area. The formula for surface area is: Surface Area=2(width x length)+2(length x height)+2(height x width) Since the question gives us the values of height, length and width. Just fill the information into the formula. Surface Area=2(7x10)+2(10x3)+2(3x7) Solve the parentheses: Surface Area= 2(70)x2(30)+2(21) Distribute the 2 into the parentheses: Surface Area=140+60+42 Solve: Surface Area=242
