Last year, Star City had all car maintenance on the city's automobiles done by the city. The cost was $364 per car. This year, the city fired all the workers in the maintenance pool and are contracting a private business for maintenance. They would like to know whether the private business is saving them money. A random sample of 36 cars showed a mean repair cost of $330, with a standard deviation of $120. What can you tell the city officials?

1. State Ho and Ha formally and in "English" (e.g. Ho: u = 20 Ha: u <> 20; Ho: The average (variable name) is 20 Ha: The average "variable name" is NOT 20. !
2. Show the math
3. Reject or retain the Ho at a = .05; provide the "critical t" value at that level
4. All tests must be two-tail
5. Clarify the findings

This process is doing backflips in my brain. Any points or tips to properly frame the procedure would be very helpful.