Enter the following 3 matrices into Matlab,

A =

-47	36	38	30
-31	6	-42	-39
-11	41	31	-40
22	-31	-14	-49
-49	-42	43	-17

, B =

30	-40	-23	38
47	-9	6	-20

, C =

15	37
13	46
47	-23
-24	39
-30	46

To check that you have correctly entered these matrices into Matlab, verify that

A^TCB =

-222966	66092	-10139	60206
20098	-159676	-119483	222382
24881	-22817	-10963	16166
-123009	32153	-8969	39602

, and that tr (A^TCB) = -354003.

(a)	Let D = CBAT. Find d15 (i.e., find the entry in row 1, column 5 of the matrix D)

(b)	Let E = ABTCT. Find tr (E)

(c)	Let F be the reduced row echelon form of ATCB. Find f14. (i.e., find the entry in row 1, column 4, of the reduced row echelon form of ATCB)