Asurveyor on one side of a river wishes to find the distance between points a and b on the opposite side of the river. on her side, she chooses point

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?