The area of the base is given by: A1 = (1/2) * (15) * (13) A1 = 97.5 The area of the lateral faces is given by: A2 = (1/2) * (15) * (10) A2 = 75 Then, the total surface area is: A = A1 + 3A2 Substituting values: A = 97.5 + 3 * (75) A = 322.5 Answer: The surface area of the equilateral triangular pyramid is: C) 322.5 in2