1. Suppose all outlets will spend $50,000 per month on advertising and maintain an average price of $10.00. Estimate the mean monthly sales among all outlets.
2. By how much, plus or minus, do you expect your estimate in the preceding question will miss actual mean monthly sales? [Be precise]
3. Can you give an interval in which you are approximately 95% confident that actual mean monthly sales will lie? [Be precise]

Context: A random sample of 15 pizza outlets were selected from the national population of outlets of a large chain of retail pizza makers. Data on monthly sales (number of pizzas), price per pizza, and advertising expenses per outlet are in the table below. You may use SAS to answer the questions above. Assume the validity of the regression model.