One local hockey team conducts a study to compare the amount of money spent on refreshments at the Bell Centre. Two simple random samples of 100 men and 100 women are collected. For men, the average...

One local hockey team conducts a study to compare the amount of money spent on refreshments at the Bell Centre. Two simple random samples of 100 men and 100 women are collected. For men, the average expenditure was $20, with a known population standard deviation of $5. For women, it was $30, with a known population standard deviation of $4.

1. 
   

   a) Estimate the difference in the expenditure between man and women using a 99% confidence interval.

   
   


2. 
   

   b) Based on your confidence interval, do you think there is a significant difference between the expen- diture of men and women? Explain.