Based upon your answer to (lo), what should the manager do to the size of the sample : increase it or decrease it? Based upon your answer to (1p), what should the manager do to the confidence level: increase it to 99% or decrease it to 90%? 3. Download the Games on Kickstarter data set that you used earlier in the semester. Recall that this data set is a sample of boardgame projects. Refresh your memory regarding the TIME variable. Our goal is to create a 95% confidence interval for the average playing time of all boardgame projects. a. First, you'll need to calculate the sample mean, sample standard deviation, and the number of observations for the TIME variable. (You learned how to do this in Lab Activity 4. Be certain to calculate the number of observations - don't simply look at the number of rows.) b. Enter these values into your worksheet to calculate the margin of error and confidence limits for a 95% confidence interval. When entering the values of the mean and standard deviation, be certain to keep at least 5 decimal places. Record the margin of error and the confidence limits rounding your answers to 3 decimals 1. A financial advisor is looking at the prevalence of free checking. In particular, the advisor is interested in the percentage of banks that offer free checking for accounts under $1,000. Since a census of all banks would be impossible, the advisor decides to calculate a 90% confidence interval for the percentage using a sample 52 banks. In the sample of 52 banks, 19 offered free checking for accounts under $1,000. In this section, you'll create a worksheet that can calculate a confidence interval for a population proportion. Create a new blank worksheet. Change the name to "pi." b. You will need to give Excel the value of the sample proportion