1.	Which of the following numbers is composite?
		A.	1	B.	23
		C.	31	D.	9
		Hint
	2.	Write the prime factorization of 1500.
		A.	22 × 3 × 53	B.	2 × 3 × 5
		C.	22 × 3 × 52 × 102	D.	22 × 3 × 52
		Hint
	3.	What are the prime factors of 400?
		A.	2, 5	B.	2, 4, 5
		C.	2, 200	D.	4, 10, 10
		Hint
	4.	Write the prime factorization of 810.
		A.	2 ×3 × 5	B.	2 × 34 × 5
		C.	32 × 4 × 5	D.	2 × 5 × 92
		Hint
	5.	Factor 20ef.
		A.	4 · 5 · e · f	B.	2 · 10 · e · f
		C.	22 · e · f	D.	2 · 2 · 5 · e · f
		Hint