THE BRANCH MANAGER OF AN OUTLET (STORE 1) OF A NATIONWIDE CHAIN OF PET SUPPLY STORES WANTS TO STUDY CHARACTERISTICS OF HER CUSTOMERS. IN PARTICULAR, SHE DECIDES TO FOCUS ON TWO VARIABLES: THE AMOUNT OF MONEY SPENT BY CUSTOMERS AND WHETHER THE CUSTOMERS OWN ONLY ONE DOG, ONLY ONE CAT OR MORE THAN ONE DOG AND/OR CAT. THE RESULTS FROM A SAMPLE OF 70 CUSTOMERS ARE AS FOLLOWS: A) AMOUNT MONEY SPENT: SAMPLE MEAN = $21.34, SAMPLE STANDARD DEVIATION = $9.22; B) 37 CUSTOMERS OWN ONLY A DOG; C) 26 CUSTOMERS OWN ONLY A CAT; D) 7 CUSTOMERS OWN MORE THAN ONE DOG AND/OR CAT.

4. CONSTRUCT A 95% CONFIDENCE INTERVAL ESTIMATE FOR THE POPULATION MEAN AMOUNT OF MONEY SPENT IN THE PET SUPPLY STORE.