"Complete the following three questions for section 1 of Business Statistics" (attached below)

The mean number oftravel days per year for salespeople employed bylhree hardware distributors needs to be estimated with a 0.95 degree of condence. For a small pilot study, the mean was 150 days and the standard deviation was i4 days, lfthe population mean is estimated within two days. how many salespeople should be sampled? Multiple Choice Q a 2,980 7'31 O O 572 O A research firm needs to estimate within 3% the proportion ofiunior executives leaving large manufacturing companies within three years A 095 degree of confidence is to be used Several years ago, a study revealed that 27% ofjunior executives left their company Within three years, To update this study, how manyiunior executives should be surveyed? Multiple Choice 0 727 1,030 745 842 000 A random sample of 42 college graduates revealed that they worked ah average of 6.3 years on tnejob before being promoted. The sarnple standard dewation was 1.9 years. Using the O 99 degree of condence what is the confidence interval forthe population mean? Multiple Choice 0 2.90 and 10.03 4 87 and 7.73 5.5l and 7.09 O 5.53 and 707