The prime factorizations of 54 and 72 are shown below. Prime factorization of 54: 2, 3, 3, 3 Prime factorization of 72: 2, 2, 2, 3, 3 Using the prime factorizations, what is the greatest common factor of 54 and 72
1.2'3
2. 2' 3'3
3.2'2' 3'3
4.2'2'2'3'3'3​