Random sample of 25 tourists visit Hawaii this summer spent on average $1420 on this trip with the standard deviation of $285. Assume that the money spent by all tourists visit Hawaii has an approximate normal distribution.
A) The 95% confidence interval for the mean money spent by all tourists visit Hawaii is:
B) Suppose the confidence interval obtained is too wide. How can do width of this interval be reduced? Discuss all possible alternatives. Which alternative is the best?