Suppose that a word is any string of six letters. Repeated letters are allowed. For our purposes, vowels are the letters a, e, i, o, and u. a) How many words are there? b) How many words begin with a vowel? c) How many words begin with a vowel and end with a vowel? d) How many words have no vowels? e) How many words have exactly one vowel?

You pick cards one at a time without replacement from an ordinary deck of 52 playing cards. What is the minimum number of cards you must pick in order to guarantee that you get a) three of a kind (for example, three 7s), and b) all four aces