A total of 300 observations of Bob Ramos, an assembly-line worker, were made over a 40-hour workweek. The sample also showed that Bob was busy working (assembling the parts) during 250 observations.a) Find the percentage of time Bob was working.b) If you want a confidence level of 95%, and if {3% is an acceptableerror, what size should the sample be?c) Was the sample size adequate?

Use the given data to find the minimum sample size required to estimate a population proportion or percentage. Margin of error: 0.06; confidence level 90%; p and q unknown ..... (Round up to the nearest integer.) n=

A) What proportion of commercial airline pilots are more than 40 years of age? Suppose an analyst has access to a list of all pilots who are members of the Air Line Pilots Association. If this list is used as a frame for the study, she can randomly select a sample of pilots, contact them, and ascertain their ages. From 89 of these pilots so selected, she learns that 48 are more than 40 years of age. Construct an 85% confidence interval to estimate the population proportion of commercial airline pilots who are more than 40 years of age. B) Suppose you want to estimate the proportion of cars that are sport utility vehicles (SUVs) being driven in Regina at rush hour by standing on the corner of Victoria Avenue and Albert Street and counting SUVs. You believe the figure is no higher than 0.40. If you want the error of the confidence interval to be no greater than 0.03, how many cars should you randomly sample? Use a 90% level of confidence.

In a sample of 7 observations, the values are 17, 11, 12, 13, 14, 15. 16. Find the 95% confidence interval for the population mean. O A. (5.00, 9.00) O B. (4.00, 8.00) OC (12.00, 16.00) OD.(11.00, 15.00)