Which angle pairs in the diagram are supplementary angles? Check all that apply. ∠3 and ∠6

∠1 and ∠4

∠5 and ∠6

∠4 and ∠5

∠6 and ∠7

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?