1.Researchers collected data on the ages of people who died, over a 1-year period, due tocardiac arrest. The distribution of the ages is normal, and the mean age was 61, with astandard deviation of 5.

(a) What percentage of people who died were between the agesof 57 and 69?

(b) What percentage of people who died were older than 69?

2.The average age of licensed drivers in a county is Mean= 42.6, Sigma= 12, and the distributionis approximately normal. A county police officer was interested in whether the averageage of drivers receiving parking tickets differed from the average age of the drivingpopulation. She obtained a sample ofN= 25 drivers receiving parking tickets. Theaverage age of these drivers wasM= 40.5. Perform the six steps of hypothesis testingnecessary to determine whether this group differs from the population of drivers in thecounty.

3.It is known that in 2013 the population mean for the writing section of the SAT is 488,with a standard deviation of 114. A sample of 100 students taking the SAT whosefamily income was less than $20,000 had a verbal score of 429.

(a) Perform a two-tailedhypothesis test to determine whether the group whose family income was less than$20,000 scored significantly differently on average than the population

(b) Assume thatrather than a sample of 100, the sample size was only 10. Perform the same hypothesistest again with this new sample size. Does the conclusion differ from what was found in(a)?