Early homework for Wednesday, September 4

If you submitted these by 5:00 pm Wednesday, you don't have to turn in 1.3, #13 and 12, 1.4 #8, 1.5 #15, or 1.7 #29 on Friday.
These problems will deal with the following matrices:
A=
15050-1
00120-2
000011
,
B=
104
0-1-3
00-3
,
C=
-3-35
004
000
,
D=
-2-4-3-4
01-20
0021
,
and M=
14-3-3-27
15-1-4-22
-315-426
.
Recall that we've seen M before. If you think they're relevant, you may cite earlier results about M without deriving them again.

Question 1:Give all solutions to the equation Ax=0, in parametric vector form.

Question 2:Which of the matrices A, B, C, D, and M above have columns that span all of R3? Justify your answer. (One sentence should suffice, at least if it's the right sentence.)

Question 3:Which of the matrices A, B, C, D, and M above have linearly independent columns? Justify your answer. (One sentence should again suffice.)