(1 point) You would like to know what the average weight of a box of bananas from Costa Rica. You know that the weight of a box of bananas is normally distributed, but you do not know the mean or standard deviation. So you take a random sample of 19 boxes of bananas delivered to a grocery store warehouse. The mean weight of the sample of boxes of bananas is 50 pounds and the samples standard deviation is 3 pounds.

(a)Give the critical value you need for a90% confidence interval for the population mean.:

Critical value:

(b)Construct a90% confidence interval for the population mean.

(c)Give the critical value you need for a99% confidence interval for the population mean.:

Critical value:

(d)Construct a99% confidence interval for the population mean.