1.A telephone survey uses a random digit dialing machine to call subjects. The random digit dialing machine is expected to reach a live person 15% of the time.

a.True or False:Each call is an independent random event.

In two attempts, what is the probability of achieving......

b.exactly two successful calls? (success = reach a live person)

c.one success and one failure (in any order)?

I'm having trouble with part b. The trouble is determining the binomial coefficient to use in my formula. I've tried looking in my text and online but I need it explained in words I can understand. Thanks