Question 2 (Statistics) The Healthy Drinks store stated that the average consumption of water per da

Question 2 (Statistics)

The Healthy Drinks store stated that the average consumption of water per day was at least 100 gallons To test the hypothesis that this figure may no longer be true, a researcher randomly selected 150 people and found that they used on average 105 gallons per day and s=10 gallons

a) At ? = 01, is there enough evidence to say that their statement might no longer be correct?

b) What are the lower-limit and the upper-limit of the 90% two-sided confidence interval?