Question 7 (Mandatory) (4 points) The Wechsler IQ test is designed so that the mean is 100 and standard deviation is 15 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students, We want to be 9525 confident that our sample mean is within 2 IQ points of the true mean. 374 373 55 153 217 Question & (Mandatory) (1 point) In estimating true population mean in a researcher took a sample of n = 35 and found a sample mean of 30.5 and sample standard deviation of 4.2. He constructed 5 confidence intervals with difference confidence levels. Which of the confidence intervals will have the shortest width? 80% 98% 95% 99% 90%