Show steps to these statistics problems, please

Problem 5: The General Social Survey has asked subjects, "How long have you lived in the city, town, or community where you live now?". The responses of 1,415 subjects in one survey had a mode of less than 1 year, a median of 16 years, a mean of 20.3, and a standard deviation of 18.2. a. Do you think that the population distribution is normal? Why or why not? b. Based on your answer in part a, can you construct a 95% confidence interval for the population mean? If not, explain why not. If so, do so and interpret. Problem 6: Increasing the confidence level causes the margin of error of a confidence interval to (a) increase, (b) decrease, (c) stay the same. Problem 7: Suppose a 95% confidence interval for the population proportion of students at your school who reg- ularly drink alcohol is (0.61, 0.67). The inference is that you can be 95% confident that the sample proportion falls between 0.61 and 0.67