In order to control costs a company wishes to study the amountof money its sales force spends entertaining clients. Thefollowing is a random sample of six entertainment expenses (dinnercosts for four people) from expense reports submitted by members ofthe sales force.$157 $132 $109 $145 $125 $139a Calculate x s2 and s for the expense data. In addition dhowthat the two different formulas for calculating s2 give the sameresult.b. Assuming that the distribution of entertainment expenses isapproximately normally distributed calculate estimates oftolerance intervals containing 69.26 percent 95.45 percent and99.73 percent of all entertainment expenses by the sales force.c. If a member of the sales force submits an entertainment expense( dinner cost for four) of $190 should this expense be consideredunusually high (and possibly worthy of investigation by thecompany)?Explain your answer.d Compare and interpret the z-score for each of the sixentertainment expenses.