1. You randomly select 18 adult male athletes and measure the resting heart rate of each. The sample mean heart rate is 64 beats per minute, with a sample standard deviation of 2.5 beats per minute....

1. You randomly select 18 adult male athletes and measure the resting heart rate of each. The sample mean heart rate is 64 beats per minute, with a sample standard deviation of 2.5 beats per minute. Assuming the heart rates are normally distributed, should you use the standard normal distribution,

the t@ distribution, or neither to construct a 90% confidence interval for the population mean heart rate? Explain your reasoning.

a. Is s known?

b. Is either the population normally distributed or n Ú 30?

c. Decide which distribution to use, if any, and explain your reasoning.