4. (20 pts, 5 pts for each) Let A1, ..., A5 be matrices with dimension 5 x3, 3 4,4 x 2, 2 3,3 x 1, respectively. Let Ci,j be the smallest number of scalar multiplications needed for computing the matrix product AiAi+1 Aj, assuming that multiplying an r x s matrix and an s x t matrix take rst scalar multiplications. Mark by T(=True) or F(=False) each of the following statements: -1... (1) In the algorithm presented in class, C3,5 is computed before C1,4. (2) C2,4 = 24. (3) C1,4 is derived from C1,3 and C4,4. (4) The optimal order to multiply A1,. A5 with fewest number of scalar multiplications is (A1(A2(A3(A4 A5))))