4. (12 pts, 3 pts for each) (Not covered) Let A1,,A5 be matrices with dimension 24,4 3,32,21,15, respectively. Let Ci,j be the smallest number of scalar multiplications needed for computing the matrix product AiAi+1Aj, assuming that multiplying an rs matrix and an st matrix take rst scalar multiplications. Mark by T(= True ) or F(= False ) each of the following statements: (1) Using the algorithm presented in class, C1,4 is computed before C3,5. 1 (2) C2,3=24. (3) C2,5 is derived from C2,4 and C5,5. (4) The optimal order to multiply A1,,A5 with fewest number of scalar multiplications is (((A1)((A2A3)A4))A5)