1.	Determine which matrix is the 3 × 3 identity matrix.
		A.		B.
		C.		D.
		Hint
	2.	If , find I so that
		A.		B.
		C.		D.
		Hint
	3.	If , find N -1.
		A.		B.
		C.		D.
		Hint
	4.	Determine whether the pair of matrices are inverses.
		A.	no, because A · B I
		B.	no, because fractions cannot be a part of an inverse
		C.	yes, because each entry in the second matrix is the reciprocal of its corresponding entry in the first matrix
		D.	yes, because A · B = I
		Hint
	5.	In order for a matrix to have an inverse, what must be true?
		A.	ad – bc 1	B.	ad – bc 0
		C.	ad – bc = 1	D.	ad – bc = 0
		Hint