The concentration of benzene was measured in units of milligrams per liter for a simple random sample of five specimens of untreated wastewater produced at a gas field. The sample mean was 7.8 with a...

The concentration of benzene was measured in units of milligrams per liter for a simple random sample of five specimens of untreated wastewater produced at a gas field.  The sample mean was 7.8 with a sample standard deviation of 1.4.  Seven specimens of treated waste water had an average benzene concentration of 3.2 with a standard deviation of 1.7.  Answer the following questions to test that the mean benzene concentration is less in treated waster than in untreated water. Use the level of significance=0.05

Sample1=untreated water, Sample2=treated water

(a) Find the test statistic.

(b) Find the p-value.

(c) State whether "reject H0" or "do not reject H0".  Input as

"reject"

or
"do not reject"
.