In exercises 1-2, determine whether the matrix is in row echelon form, reduced row echelon form, both, or neither.
a. [1 0 0]
[0 1 0]
[0 0 1]
b. [1 0 0]
[0 1 0]
[0 0 0]
c. [0 1 0]
[0 0 1]
[0 0 0]
d. [1 0 3 1]
[0 1 2 4]
e. [1 2 0 3 0]
[0 0 1 1 0]
[0 0 0 0 1]
[0 0 0 0 0]
f. [0 0]
[0 0]
[0 0]
g. [1 -7 5 5]
[0 1 3 2]