Hi Can I please get hep with the following questions. Can I also get help on how to process on excel with formulas?

Confidence

1.The daily sales of Burger Baby restaurants follow the normal distribution with a standard deviation of $4000.

a. A sample is taken of 50 restaurants and the average sales were $40,000/day.

What is the 99% confidence interval for the average restaurant sales?

b. What is the probability that the average sales are really $36,000 or less per day?Assume the actual population average is $40,000 per day

2.Sample of the sales at 50 Haute Dog restaurants is taken and the sample mean is $30,000 per daywith asamplestandard deviation of $2000.The population standard deviation is not known.

a. What is the 90% confidence interval for the daily sales at all restaurants.

b. What is the probability that the average sales are really $32,000 or more per day?Assume that the population average is $30,000 per day and the std. Deviation is $2k.