Which of the following best shows the associative property of addition? Group of answer choices

4 + 5 + 2 = 2 + 5 + 4

4 + 5 = 5 + 4

(4 + 5) + 2 = 4 + (5 + 2)

4 + 5 = 9

Aparticular telephone number is used to receive both voice calls and fax messages. suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (a) what is the expected number of calls among the 25 that involve a fax message?