What conclusion can you draw about a negative number raised to an odd power

The random variable x represents the number of phone calls an author receives in a day, and it has a poisson distribution with a mean of 8.7 calls. what are the possible values of x

Bob is putting books on a shelf and takes a break after filling 18 1/2 inches on the book shelf. the book shelf is now 2/3 full. how long is the entire bookshelf?

Find an bif a = {3, 6, 9, 12) and b = {2, 4, 6, 8, 10).