The following is a random sample of 6 sums of money spent on textbooks from students MAT158 who needed to spend money on a textbook for their class: $85 $55 $110 $77 $124 $89 a) Find the sample standard deviation of these 6 sums of money that were spent. s = (round to two decimal places) b) The table below is the collection of money spent by the entire population of MAT158 students: Money (in dollars) Frequency 0 - 49 50 - 99 2680 100 - 149 1980 150 - 199 1270 Approximate the mean sum of money that the population of MAT158 students spent on textbooks. (Round to the nearest cent, two decimal places) c) Use the table to approximate about how many MAT158 students at a school of 2500 MAT158 students spent $150 to $199 on textbooks. (Round to the nearest whole number if necessary)