1.For bone density scores that are normally distributed with a mean of 0 and a standard deviation of 1, find the percentage of scores that are.a.significantly high (or at least 2 standard deviations above the mean).b.significantly low (or at least 2 standard deviations below the mean).c.not significant (or less than 2 standard deviations away from the mean). (high 2.28%, low 2.28%, not significant 95.45%)
2.A study of the amount of time it takes a mechanic to rebuild the transmission for a 2010 ChevroletColorado shows that the mean is 8.4 hours and the standard deviation is 1.8 hours. If 40 mechanics are randomly selected, find the probability that their mean rebuild time is less than 8.9 hours. Round to four decimal places.
3.Assume that adults have IQ scores that are normally distributed with a mean of μ=105 and a standard deviation σ=15. Find the probability that a randomly selected adult has an IQ between 93 and 117.
4.Select the correct interpretation of the probability of getting an 11 when a pair of dice is rolled.