3. A major computer manufacturer is having an endof-

season sale on computers. The number of computers sold during this sale at a sample of 10 stores was 800, 1,100, 0, 400, 700, 800, 1,000, 500, 800, and 300.

a. Is there evidence that an average of more than 500 computers per store were sold during this sale? Use

.

b. What assumption is necessary to perform this test?