1) A sample of 100 is taken with a standard deviation of 2.4 units; with what probability will the true mean be within a margin of error of 0.3 units?

2) A sample of 100 peacock bass are caught and a sample mean of 6.5 pounds is noted. If the standard deviation is assumed to be 2.4 pounds, find a 95% confidence interval for the true mean size.

3) We are trying to estimate the mean size for a newly discovered bird. If the standard deviation is estimated to be 2.4cm and a margin of error of 0.5cm is needed. How large a sample is needed? Use 95% confidence.