A population has standard deviation o = 17.2. Part 1 of 2 (a) How large a sample must be drawn so that a 99% confidence interval for u will have a margin of error equal to 3.1? Round the critical value to no less than three decimal places. Round the sample size up to the nearest integer. A sample size of is needed to be drawn in order to obtain a 99% confidence interval with a margin of error equal to 3.1. Part 2 of 2 (b) If the required confidence level were 99.5%, would the necessary sample size be larger or smaller? (Choose one) V because the confidence level is (Choose one)SAT scores:.A college admissions ofcer takes a simple random sample of' 100 entering freshmen and computes their mean (a) Construct a 99% condence interval for the mean mathematics SAT score for the entering freshman class. Round the answer to the nearest whole number. A 99% condence interval for the mean mathemaos SAT score is 416.373 sf [1. 4: 475.622 . mathematics SAT score to be 4'46; Assume the population standard deviation is o = 115'. (b) If the sample size were-85 rather than IUD, would the margin of error be larger or smaller than the-result in part {a}? Explain. The margin of error would be {Choose one] 'I' 1will (choose one) 'I' the standard error. ,._since [Choose one] 1' I in the sample size Watch your cholesterol: A sample of 305 patients between the ages of 38 and 82 were given a combination of drugs ezetimibe and simvastatin. They achieved a mean reduction in total cholesterol of 0.80 millimole per liter. Assume the population standard deviation is o = 0.20. Part 1 of 3 (a) Construct an 80% confidence interval for the mean reduction in total cholesterol in patients who take this combination of drugs. Round the answer to at least two decimal places. An 80% confidence interval for the mean reduction in cholesterol is 0.785 0.815 Part: 1 / 3 Part 2 of 3 (b) Should this confidence interval be used to estimate the mean reduction in total cholesterol for patients over the age of 90? The confidence interval (Choose one) be used to estimate the mean reduction in total X cholesterol for patients should should notHowr smart is your phone? A random sample of 8 Samsung Galaxy smartpnones being sold over the Internet in 2U13 had the following prices, in dollars: 199 169 385 329 269 149 135 249 If Send data to Excel-"I- Assume the population standard deviation is o = 8]. Perform the following. Part: 0 I 3 Pattlof3 the sample size is less than or equal to 30 population is approximately normal before constructing a confidence the sample standard deviations not known the population mean is not known the Houlation standard deviation is not known nproximately normal because [Choose one) V . X b lifetime of electronim: In a simple random sample of 100 electronic components produmad- by a certain method, the mean lifetime was 125 hours. Assume that component lifetimes-are normally distributed with populaon standard deviation 0 = 20 hours. Round the critical value to no less than three decimal places. (a) Construct an 80% condence interval for the mean batten.r life. Round the answer to the nearest whole number; An 80% oonfidence interval for the mean battery life is 122.43?