PART A ONLY DO PART B PART A IS HERE FOR REFERENCE

1.What is a confidence-interval estimate of a parameter? Why is such an estimate superior to a point estimate?

2.Explain the similarities and differences between a standard normal distribution and the Student's t distribution.

3.Must the variable under consideration be normally distributed for you to use the z-interval procedure or t-interval procedure? Explain your answer. (2 marks)

4.If you obtained one thousand 95% confidence intervals for a population mean, roughly how many of the intervals would actually contain m?

5.The following table gives the age (in years) of 36 randomly selected U.S. millionaires. The sample mean 58.53 years. Assume that the standard deviation of the ages of all U.S. millionaires is 13.0 years.

\f31 45 79 64 48 38 39 68 52 59 68 79 42 79 53 74 66 66 71 61 52 47 39 54 67 55 71 77 64 60 75 42 69 48 57 48\fA B BP 2 81.6 3 84.1 4 87.6 5 82.8 6 82 7 88.9 8 86.7 9 96.4 10 84.6 11 101.9 12 90.8 13 94 14 69.4 15 78.9 16 75.2 17 91 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Sheet1