128 Where will you get your next pet? 50% of pet owners will get their next dog or cat from a Shelter ( USA Today , May 12, 2010). In a random sample of 200 pet owners, let x be the number who will get their next dog or cat from a shelter.

a. Find the mean of x .

b. Find the standard deviation of x .

c. Find the z -score for the value x = 110.

d. Find the approximate probability that x is less than or equal to 110.