a. The lengths 7, 40 and 41 can not be sides of a right triangle.12, 16, and 20 can not be sides of a right triangle.b. The lengths 7, 40 and 41 can not be sides of a right triangle.12, 16, and 20 can be sides of a right triangle.c. The lengths 7, 40 and 41 can be sides of a right triangle. 12, 16, and 20 can not be sides of a right triangle. d.The lengths 7, 40 and 41 can be sides of a right triangle. 12, 16, and 20 can be sides of a right triangle.