Benji is conducting an experiment he has 0.78 L of solution to the body evenly among a petri dishes how much solution should you put each petri dish​

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?