a. If 5 is removed from the set of whole numbers, is the set closed with respect to addition? Explain.
A. No. For example, 2+3 = 5 and 5 does not belong to the set.
B. No. For example, 5+2 = 7 and 5 does not belong to the set.
? C. Yes. There will be no numbers in the set that will sum to 5.
D. Yes. There will be no numbers in the set that are the sum of 5 and another number.
b. If 5 is removed from the set of whole numbers, is the set closed with respect to multiplication? Explain.
A. No. For example, 2.5 × 2 = 5 and 5 does not belong to the set.
B. Yes. There will be no numbers in the set that will multiply to give a product of 5.
C. Yes. There will be no numbers in the set that are the product of 5 and another number.
D. No. For example, 5 × 1 = 5 and 5 does not belong to the set.