According to the American Pet Products Manufacturers Association (APPMA) 2003-2004 National Pet Owners Survey, 39% of U.S. households own at least one dog and 34% of U.S. households own at least one cat. Assume that 60% of U.S. households own a cat or a dog.

a. What is the probability that a randomly selected U.S. household owns neither a cat nor a dog?

b. What is the probability that a randomly selected U.S. household owns both a cat and a dog?

c. What is the probability that a randomly selected U.S. household owns a cat if the household has a dog?