Solve the given problems correctly and show the solutions in the allotted cells. 1) An electronic manufacturer produces lampshades with a life span of approximately normally distributed with a...

Extracted text: Solve the given problems correctly and show the solutions in the allotted cells. 1) An electronic manufacturer produces lampshades with a life span of approximately normally distributed with a standard deviation of 35 hours. a) If a sample of 50 bulbs has an average life span of 835 hours, construct a 95% confidence interval for the average life span of all the lampshades produced. Interpret the result. b) What must be the sample size if the manufacturer wishes to be 99% confident that the estimate is within 10 hours of the corect mean? Interpret the result. 2) A study was conducted to determine the effect of cigarette smoking on the carbon monoxide diffusing capacity of the lungs. The carbon monoxide diffusing capacities for a random sample of 20 current smokers are listed below. 106 76 109 121 98 93 85 93 98 74 95 89 73 76 62 104 108 79 103 85 Note: Round off the standard deviation to two decimal places. a) Construct a 90% confidence interval for the mean carbon monoxide diffusing capacity of current smokers. Interpret the result. b) Based on the interval in (a), would you agree that the mean diffusing capacity could be 95? Explain. 3) A certain college wants to estimate the proportion of Senior High School students who want to pursue a college course. Out of 600 random samples of Senior High School students, 321 students expressed interest to pursue a college course. Construct a 95% confidence interval for the actual percentage of students who want to pursue a college course. Interpret the result.