A diver was 5 feet below the surface of a lake. She dove to a depth of 80 feet. 15 feet
80 feet
Which integer represents the change in the diver's depth?

A.-85
B.-75
C.75
D. 85

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?