In this exercise we're going to plan and write a CC that takes one integer N and determine if it is prime. We begin with working at least one instance by hand. We might start with something like is 7 prime and you might just say, yes, I know this, 7 is prime. However, this is not very helpful. Just knowing the answer does not help us develop a step-by-step approach to solving the general problem. Learning to put the obvious aside and think about what is going on is a key programming skill to learn, but takes some time.