Hoping to lure more shoppers downtown, a city builds a new public parking garage in the central business district. The city plans to pay for the structure through parking fees. During a two-month period (44 weekdays), daily fee collected averaged $126, with a standard deviation of $15.

1. What assumptions must you make in order to use these statistics for interference?
2. Write 90% confidence interval for the mean daily income this parking garage will generate.
3. Interpret this confidence interval in context.
4. Explain what "90% confidence" means in this context.
5. The consultant who advised the city on this project predicted that parking revenue would average $130 per day. Based on your confidence interval, do you think the consultant was correct? why?