【多选题】If U is the reduced row echelon form of a square matrix A,then .
A.
A and U have the same column space.
B.
A and U have the same null space.
C.
A and U have the same rank.
D.
A and U have the same nullity.
E.
A and U have the same value of their determinants.
F.
A and U have the same row space.