please help answer these questions

An IQ test is designed so that the mean is 100 and the standard deviation is 18 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of the residents of a state if you want to be 95% confident that the sample mean is within 4 IQ points of the true mean. The required sample size is _. (Round up to the nearest whole number.)Suppose you conducted an opinion poll and measured the proportion of your sample that held a particular view. What value should you use as your estimate oi the population proportion? Choose the correct answer below. 0 A. The sample standard deviation multiplied by the square root of the sample size 0 B. The sample proportion dwided by the square root of the sample size 0 C. The sample proportion O D. The sample proportion dwided by the sample size The health of the bear population in a park is monitored by periodic measurements taken from anesthetized bears. A sample of the weights of such bears is available below. Use a single value to estimate the mean weight of all such bears. Find a 95% confidence interval estimate of the mean of the population of all such bear weights. Click the icon to view the table of bear weights. The estimate of the population of all such bear weights is pounds. (Round to one decimal place as needed.) X Bear weights Find the 95% confidence interval for the mean of the population of all such bear weights. pounds