Pure-Bred Dogs Competing in Shows Must Often Meet Specific Height

Question 101

Pure-bred dogs competing in shows must often meet specific height criteria to be within the breed standard.A new breed of dog,the pug-cock-a-poo,has been approved by a kennel club.To establish the breed standard,the organization of breeders has taken the height from a sample of 25 pug-cock-a-poos and found the sample mean to equal 14 inches.The variance of this sample is 2.25.a.Construct a 90% confidence interval for the population mean height of the pug-cock-a-poos.b.What assumption is necessary for constructing the aforementioned interval?