4: A certain airplane has two independent alternators to provide electrical power. The probability that a given alternator will fail on a one-hour flight is .02. What is the probability that (a) both will fail? (b) Neither will fail? (c) One or the other will fail? Show all steps carefully. Question 5: Dave the jogger runs the same route every day (about 2.2 miles). On 18 consecutive days, he recorded the number of steps using a pedometer. The results were 3,450 3,363 3,228 3,360 3,304 3,407 3,324 3,365 3,290 3,289 3,346 3,252 3,237 3,210 3,140 3,220 3,103 3,129 (a) Construct a 95 percent confidence interval for the true mean number of steps Dave takes on his run. (b) What sample size would be needed to obtain an error of 20 steps with 95 percent confidence? (c) Using Excel, plot a line chart of the data. What do the data suggest about the pattern over time