I want an explanation for this example

The Speedy Oil Change Company advertised 19-minute wait for an oil change. A sample of 20 oil changes showed a mean time of 19.7 minutes and from previous studies it is known that the population standard deviation is 1.8 minutes. At the 5% level of significance, is there evidence that the mean time for an oil change is more than 19 minutes? Assume the data is normally distributed. Perform the following steps of hypotheses testing and draw a conclusion.

1. State the hypothesis. Use these symbols >, <, =,

Ho:

Ha:

2. We should use --------- distribution. (fill in the blank using z or t)

3. Type of test: tailed test (fill in the blank using left, right, or two

4. Find the critical value(s). Use if needed

Critical value(s) =

5. Test statistic or test value rounded to two decimal places =

6. Make the decision.

Since the test statistics falls under the -------------- region (Fill in the blank with these words: acceptance, or critical), we ------------------ the null hypothesis. (fill in the blank with these words: reject, or fail to reject)

7.Summarize the results

Therefore, there is ----------- evidence to ------------ the given claim. (Fill in the blank with enough or not enough, and support, or reject)