The reformer unit in a refinery produces an octane number of 90 under an existing (old) catalyst. A new catalyst has been developed and used in the unit. An average octane number of 89 has been estimated using a sample of 10 data points using this new catalyst. Use a hypothesis test at the 10% significance level. From past experience, we know that the standard deviation for octane number (in octane units) is 1.4 and we are willing to assume that the variance hasn't changed. What is the test statistics Select one: a. -2.26 O b. -2.62 Oc 2.62 Find text or tools Q d. 2.26