7.2(11b)

A company claims that the mean monthly residential electricity consumption in a certain region is more than

890

kiloWatt-hours (kWh). You want to test this claim. You find that a random sample of

62

residential customers has a mean monthly consumption of

910

kWh. Assume the population standard deviation is

126

kWh. At

=0.10,

can you support the claim? Complete parts (a) through (e).

Question content area bottom

Part 1

(a) Identify

H0

and

Ha.

Choose the correct answer below.

A.

H0:

890

Ha:

>890

(claim)

Your answer is correct.

B.

H0:

=890

(claim)

Ha:

890

C.

H0:

910

Ha:

>910

(claim)

D.

H0:

=910

Ha:

910

(claim)

E.

H0:

>910

(claim)

Ha:

910

F.

H0:

>890

(claim)

Ha:

890

Part 2

(b) Find the critical value(s) and identify the rejection region(s). Select the correct choice below and fill in the answer box within your choice. Use technology.

(Round to two decimal places as needed.)

A.

The critical values are

enter your response here.

B.

The critical value is

enter your response here.