More pets. You're thinking about getting two dogs and a cat. Assume that annual veterinary expenses are independent and have a Normal model with the means and standard deviations described in Exercise 38.

a) Define appropriate variables and express the total annual veterinary costs you may have.

b) Describe the model for this total cost. Be sure to specify its name, expected value, and standard deviation.

c) What's the probability that your total expenses will exceed $400?

Exercise 38

Pets. The American Veterinary Association claims that the annual cost of medical care for dogs averages $100, with a standard deviation of $30, and for cats averages $120, with a standard deviation of $35.

a) What's the expected difference in the cost of medical care for dogs and cats?

b) What's the standard deviation of that difference?

c) If the costs can be described by Normal models, what's the probability that medical expenses are higher for someone's dog than for her cat?

d) What concerns do you have?