The file German Coffee contains a random sample of 144 German coffee drinkers and measures the annual coffee consumption in kilograms for each sampled coffee drinker. A marketing research firm wants to use this information to develop an advertising campaign to increase German coffee consumption.

a. Based on the sample’s results, what is the best point estimate of average annual coffee consumption for German coffee drinkers?

b. Develop and interpret a 90% confidence interval estimate for the mean annual coffee consumption of German coffee drinkers.