Part a 3 points The following information is given The sampl

Part (a)            (3 points)
The following information is given:

The sample consists of 119 cars driving down Browndale Highway. Their mean speed is 42 miles per hour.

= 0.05

The test statistic has a standard normal distribution (if H₀ is true).

If it is possible to determine the critical value(s) based on this information, determine it/them. If it is not possible, explain why it is not possible.

Part (b) is independent from Part (a), i.e., do not use information from Part (a) to answer Part (b).

The following information is given:

= 0.10

The null hypothesis is that the mean thickness of a certain kind of wire is 0.5 millimeters.

The test statistic has a standard normal distribution (if H₀ is true).

If it is possible to determine the critical value(s) based on this information, determine it/them. If it is not possible, explain why it is not possible.

Solution

(a)

It is not possible to determine the critical values. The critical values involve the standard deviation term. No information regarding population or sample s.d. is given. Hence the critical values cannot be computed.

(b)

It is not possible to determine the critical values. The critical values involve the standard deviation term. No information regarding sample mean and population or sample s.d. is given. Hence the critical values cannot be computed.