A used car dealer says that the mean price of a three-year-old sports utility vehicle (in good

Question:

A used car says that the mean price of a three-year-old sports utility vehicle (in good condition) is $20,000. You suspect this claim is incorrect and find that a random sample of 22 similar vehicles has a mean price of $20,640 and a standard deviation of $1990. Is there enough evidence to reject the claim at α = 0.05?
(a) Identify the claim and state H0 and Ha,
(b) Find the critical value(s) and identify the rejection region(s),
(c) Find the standardized test statistic t,
(d) Decide whether to reject or fail to reject the null hypothesis,
(e) Interpret the decision in the context of the original claim. Assume the population is normally distributed. If convenient, use technology.
Dealer
A dealer in the securities market is an individual or firm who stands ready and willing to buy a security for its own account (at its bid price) or sell from its own account (at its ask price). A dealer seeks to profit from the spread between the...