1.) Construct a 95% confidence interval estimate for the population standard deviation, , of the annual salaries of software engineers if a sample of 14 randomly selected software engineers has a standard deviation of $3725. a) Determine 2 and 2 . b) Write down the formula and the calculate the confidence interval. Follow the proper rounding rules. Test the given claims by doing each of the following: a) Identify the null and alternate hypotheses, b) calculate the P-value, c) state whether to reject or fail to reject H0, d) state the conclusion about the claim. 2) A Pew Research poll of 328 randomly selected adults found that 62 of them stated that they used Instagram at least once a week. Use a 0.01 significance level to test the claim that more than 20% of adults use Instagram at least once a week.