#2 - A survey of U.S. companies that do business with firms in India asks: approximately how many years has your company been trading with firms in India? Suppose the population is normal. If the population standard deviation was known as 7.9 years, and a random sample of 11 responses yielded a mean of 10.720 years. Please construct a 90% confidence interval for the mean number of years that a company has been trading in India for this population. If we want to have a smaller margin of error, e.g., just 1.68 years, what sample size is required? Enter your answer as an integer.

If you can set this up in R, please do so. Thank you!