The stack is 3 inches high, and thus has four vertical rectangular areas 3 by 1 in^2 each, which constitutes a total vertical surface area of 4(3 in^2), or 12 in^2. Twice the area of the base is 2(1 in^2) = 2 in^2.
Combine 12 in^2 and 2 in^2: 14 in^2 is the total surface area of this 3-d object.
