A marketing director is going to test whether the latest promotion has increased sales over 200 units per week. He believes the population is normally distributed, and the standard deviation is known. If he is using an alpha of 0.10, the z value he should look up in the normal distribution table is which of the following? Question 4 options: 1) 1.28 2) 2.33 3) -1.28 4) -2.33