Dr. Susan Benner is an industrial psychologist. She is currently studying stress among executives of Internet companies. She has developed a questionnaire that she believes measures stress. A score above 80 indicates stress at a dangerous level. A random sample of 15 executives revealed the following stress level scores.

94 78 83 90 78 99 97 90 97 90 93 94 100 75 84

(a) What is the point estimate of the population mean? (Round your answer to 4 decimal places.)

Estimated population mean

(b)
Construct a 95 percent confidence level for the population mean. (Round your answers to 2 decimal places.

Confidence interval for the population mean is between and .

(c)
Is it reasonable to conclude that Internet executives have a mean stress level in the dangerous level, according to Dr. Benner's test?

An engineer is going to redesign an ejection seat for an airplane. the seat was designed for pilots weighing between 120 lb and 161 lb. the new population of pilots has normally distributed weights with a mean of 125 lb and a standard deviation of 28.1 lb. a)if a pilot is randomly selected, find the probability that his weight is between 120 lb and 161 lb.the probability is approximately? b. if 36 different pilots are randomly selected, find the probability that their mean weight is between 120 lb and 161 lb. the probability is approximately? c. when redesigning the ejection seat, which probability is more relevant? . part (b) because the seat performance for a single pilot is more important. b. part (b) because the seat performance for a sample of pilots is more important. c. part (a) because the seat performance for a sample of pilots is more important. d. part (a) because the seat performance for a single pilot is more important.