Cell phones emit radio frequency energy that is absorbed by the body when the phone is next to the ear and may be harmful. The table in the next column gives the absorption rate for a random sample of twenty cell phones. (The Federal Communication Commission sets a maximum of 1.6 watts per kilogram for the absorption rate of such energy.) Construct a 90% confidence interval for the true average cell phone absorption rate.

0.87…………………………….        0.72

1.30…………………………….        1.05

0.79…………………………….        0.61

1.45…………………………….        1.01

1.15…………………………….        0.20

1.31…………………………….        0.67

1.09…………………………….        1.35

0.66…………………………….        1.27

0.49…………………………….        1.28

1.40…………………………….        1.55