Collete is self-employed, selling stamps at home parties. She wants to estimate the average amount a client spends at each party. A random sample of 35 clients' receipts gave a mean of $34.70 with standard deviation s=$4.85. a. Find a 90% confidence interval for the average amount spent by all clientsb. What conditions are necessary for your calculations?b. For a party with 35 clients, use part (a) to cstimate a range of dollar values for Collete's total sales at that party.