Please find The critical value(s)

r 9 Homework Question 5, 9.3.47-T HW Score: 29.71%, 2.67 of 9 points Part 3 of 6 Points: 0.33 of 1 Save A report states that the cost of repairing a hybrid vehicle is falling even while typical repairs on conventional vehicles are getting more expensive. The most common hybrid repair, replacing the hybrid inverter assembly, had a mean repair cost of $3,927 in 2012. Industry experts suspect that the cost will continue to decrease given the increase in the number of technicians who have gained expertise on fixing gas-electric engines in recent months. Suppose a sample of 100 hybrid inverter assembly repairs completed in the last month was selected. The sample mean repair cost was $3,850 with the sample standard deviation of $400. Complete parts (a) and (b) below. a. Is there evidence that the population mean cost is less than $3,927? (Use a 0.01 level of significance.) State the null and alternative hypotheses . Ho: H 2 $ 3,927 Hy: u