What is the range of the function on the graph? all real numbers all real numbers less than or equal to –1 all real numbers less than or equal to 3 all real numbers less than or equal to 0

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?