Question: 1. Let f: Z → Z be defined by f(x) = x . Is f one-to-one? Is f onto? Explain why or why not in each case.
2. (Donated by Dave Perkins) A small skunk stumbles upon a plover's nest that contains six eggs. The skunk is only able to choose three of the six eggs to take with her; how many choices total does she have? (Fortunately for the eggs, the plover returns while the skunk is calculating and chases the skunk away.)