Find test statistics and conclusion also please

In preparation for upcoming wage negotiations with the union, the managers for the Bevel Hardware Company want to establish the time required to assemble a kitchen cabinet. A first line supervisor believes that the job should take 59 minutes on average to complete. A random sample of 21 cabinets has an average assembly time of 55 minutes with a population standard deviation of 9 minutes. Is there overwhelming evidence to contradict the first line supervisor's belief at a 0.01 significance level? Assume the population of assembly times is approximately normally distributed. Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Ho : H = 59 Ha : H