Refer to the U.S. Army Corps of Engineers data on contaminated fish saved in the DDT file. Recall that the length (in centimeters), weight (in grams), and DDT level (in parts per million) were measured for each of 144 fish caught from the polluted Tennessee River in Alabama. 

a. An analysis of the data reveals that the distribution of fish lengths is skewed to the left. Assume that this is true of the population of fish lengths and that the population has mean μ = 43 centimeters and σ = 7 centimeters. Use this information to describe the sampling distribution of y̅, the mean length of a sample of n = 40 fish caught from the Tennessee River.

b. An analysis reveals that the distribution of fish weights is approximately normal. Assume that this is true of the population of fish weights and that the population has mean μ = 1,050 grams and σ = 376  grams. Use this information to describe the sampling distribution of Y̅, the mean weight of a sample of n = 40 fish caught from the Tennessee River.

c. An analysis reveals that the distribution of fish DDT levels is highly skewed to the right. Assume that this is true of the population of fish DDT levels and that the population has mean μ = 24 ppm and σ = 98 ppm. Use this information to describe the sampling distribution of Y̅, the mean DDT level of a sample of n = 40 fish caught from the Tennessee River.