Can anyone help explain these to me correctly? I am stuck on how to do it

1) Sales of a new line of athletic footwear are crucial to the success of a newly formed 1 ) company. The company wishes to estimate the average weekly sales of the new footwear to within $150 with 99% reliability. The initial sales indicate that the standard deviation of the weekly sales figures is approximately $1550. How many weeks of data must be sampled for the company to get the information it desires? 2) The following data represent the scores of 50 students on a statistics exam. The mean score 2) is 80.02, and the standard deviation is 11.9. 39 51 59 63 66 68 68 69 70 71 71 71 73 74 76 76 76 77 78 79 79 79 79 80 80 82 83 83 83 85 85 86 86 88 88 88 88 89 89 89 90 90 91 91 92 95 96 97 97 98 What percentage of the scores lies within one standard deviation of the mean? two standard deviations of the mean? three standard deviations of the mean? Based on these percentages, do you believe that the distribution of scores is mound -shaped and symmetric? Explain