Need help with the ones that are marked wrong. Thank you.

3 The highway fuel economy of a 2016 Lexus RX 350 FWD 6-cylinder 3.5-L automatic 5-speed using premium fuel is a normally distributed random variable with a mean of / = 21.00 mpg and a standard deviation of o = 3.25 mpg. 5 (a) What is the standard error of points X the mean from a random sample of 16 fill-ups by one driver? (Round your answer to 4 decimal places.) Standard error of 0.8125 (b) Within what interval would you expect the sample mean to fall, with 90 percent probability? (Round your answers to 4 decimal places.) The interval is from 19.6610 x to 22.34234 Use the sample information = 37, o = 5, n= 15 to calculate the following confidence intervals for / assuming the sample is from a normal population. points (a) 90 percent confidence. (Round your answers to 4 decimal places.) The 90% confidence interval is from 34.8731 to 39.1212 (b) 95 percent confidence. (Round your answers to 4 decimal places.) The 95% confidence interval is from 34.4700 to 39.5300 (c) 99 percent confidence. (Round your answers to 4 decimal places.) The 99% confidence interval is from 33.7500 to 403230 X6 A random sample of 25 items is drawn from a population whose standard deviation is unknown. The sample mean is = 850 and the sample standard deviation is s=15. Use Appendix D to find the values of Student's t. oints (a) Construct an interval estimate of // with 95% confidence. (Round your answers to 3 decimal places.) The 95% confidence interval is from 844.867 to 855.133 (b) Construct an interval estimate of / with 95% confidence, assuming that s = 30. (Round your answers to 3 decimal places.) The 95% confidence interval is from 839.734 x to 860.266 (c) Construct an interval estimate of / with 95% confidence, assuming that s = 60. (Round your answers to 3 decimal places.) The 95% confidence interval is from 829.468 to 870.5327 A random sample of 16 pharmacy customers showed the waiting times below (in minutes). 15 19 16 22 18 5 9 16 19 20 22 19 18 13 20 points 24 19 Click here for the Excel Data File Find a 90 percent confidence interval for /, assuming that the sample is from a normal population. (Round your standard deviation answer to 4 decimal places and t-value to 3 decimal places. Round your answers to 3 decimal places.) The 90% confidence interval 16.2879 to 19.087110 Of 54 bank customers depositing a check, 23 received some cash back. (a) Construct a 90 percent confidence interval for the proportion of all depositors who ask for cash back. (Round your answers to 4 decimal places.) points The 90% confidence interval is from 0.4185 x to 0.4333 (b) May normality of p be assumed