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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). a. The percentage of bone density scores that are significantly high is (Round to two decimal places as needed.) b. The percentage of bone density scores that are significantly low is %. (Round to two decimal places as needed.) c. The percentage of bone density scores that are not significant is 1%. (Round to two decimal places as needed.)Pulse rates of women are normally distributed with a mean of 77.5 beats per minute and a standard deviation of 11.6 beats per minute. Answer the following questions. What are the values of the mean and standard deviation after converting all pulse rates of women to z scores using 2 = u=D mm The original pulse rates are measure with units of "beats per minute". What are the units of the corresponding 2 scores? Choose the correct choice below. OA. OB. oc. OD. The 2 scores are measured with units of "minutes per beat." The z scores are measured with units of "beats per minute." The z scores are measured with units of "beats." The 2 scores are numbers without units of measurement. (X'P) ? Assume that adults have IQ scores that are normally distributed with a mean of p= 105 and a standard deviation 6 =15. Find the probability that a randomly selected adult has an [0 between 94 and 116. Click to view page 1 of the table. Click to view p_age 2 of the table. The probability that a randomly selected adult has an IQ between 94 and 116 is E. (Type an integer or decimal rounded to four decimal places as needed.) Assume a population of 4. 5. and 9, Assume that samples of size n = 2 are randomly selected with replacement from the population. Listed below are the nine different samples. Complete parts a through d below. 4,4 4.5 4,9 5,4 5,5 5,9 9,4 9,5 9,9 a. Find the value of the population standard deviation 6. o = (Round to three decimal places as needed.) b. Find the standard deviation of each of the nine samples, then summarize the sampling distribution of the standard deviations in the format of a table representing the probability distribution of the distinct standard deviation values. Use asoending order of the sample standard deviations. s Probablllty 1.0.0.5 1,2,0.707 2.525,8,4.2 1538.12.55 (Type integers or fractions.) c. Find the mean of the sampling distribution of the sample standard deviations. The mean of the sampling distribution of the sample standard deviations is (Round to three decimal places as needed.) d. Do the sample standard deviations target the value of the population standard deviation? In general, do sample standard deviations make good estimators of population standard deviations? Why or why not? 0 A. The sample standard deviations do not target the population standard deviation, therefore, sample standard deviations are unbiased estimators. O B. The sample standard deviations do target the population standard deviation, therefore, sample standard deviations are biased estimators. O C. The sample standard deviations do target the population standard deviation, therefore, sample standard deviations are unbiased estimators O D. The sample standard deviations do not target the population standard deviation. therefore. sample standard deviations are biased estimators. Assume that females have pulse rates that are normally distributed with a mean of p.= 74.0 beats per minute and a standard deviation of o = 12.5 beats per minute. Complete parts (a) through (c) below. a. lf 1 adult female is randomly selected, nd the probability that her pulse rate is less than 77 beats per minute. The probability is . (Round to four decimal places as needed.) b. If 16 adult females are randomly selected, find the probability that they have pulse rates with a mean less than 77 beats per minute. The probability is . (Round to four decimal places as needed.) c. Why can the normal distribution be used in part (b), even though the sample size does not exceed 30? O A. Since the distribution is of individuals, not sample means, the distribution is a normal distribution for any sample size. 0 B. Since the original population has a normal distribution, the distribution of sample means is a normal distribution for any sample size. O C. Since the mean pulse rate exceeds 30, the distribution of sample means is a normal distribution for any sample size. 0 D. Since the distribution is of sample means, not individuals, the distribution is a normal distribution for any sample size. When women were finally allowed to become pilots of fighter jets, engineers needed to redesign the ejection seats because they had been originally designed for men only. The ejection seats were designed for men weighing between 130 lb and 201 lb. Weights of women are now normally distributed with a mean of 164 lb and a standard deviation of 48 lb. Complete parts (a) through (c) below. a. If 1 woman is randomly selected, find the probability that her weight is between 130 lb and 201 lb. The probability is approximately . (Round to four decimal places as needed.) b. If 35 different women are randomly selected, find the probability that their mean weight is between 130 lb and 201 lb. The probability is approximately . (Round to four decimal places as needed.) c. When redesigning the ejection seat, which probability is more relevant? O A. The part (a) probability is more relevant because the seat performance for a sample of pilots is more important. O B. The part (b) probability is more relevant because the seat performance for a sample of pilots is more important. C. The part (a) probability is more relevant because the seat performance for a single pilot is more important. O D. The part (b) probability is more relevant because the seat performance for a single pilot is more important.If np 2 5 and nq 2 5, estimate P(fewer than 8) with n = 14 and p = 0.6 by using the normal distribution as an approximation to the binomial distribution; if np