need help with problem attached. 1. Benzene is a toxic chemical used in the manufacturing of medicinal chemicals, dyes, artificial leather, and linoleum. A manufacturer claims that its exit water meets the federal regulation with a mean of less than 7980 ppm of benzene. To assess the benzene content of the exit water, 10 independent water samples were collected and found to have an average of 7906 ppm of benzene. Assume a known standard deviation of 80 ppm and use a significance level of 0.01. To test the manufacturer's claim using = 0.01, a. conduct the test by going through the 8 steps of critical region approach; b. conduct the test by going through the 8 steps of P-value approach; c. Check to see if additional assumptions are needed for conducting the tests in parts (a) and (b)