In the past, a company used to produce 40 tons of a certain food per day on average. Now, using a new technology, the mean daily yield of the food for a random sample of 25 days of production is 45 tons with a standard deviation of 5 tons. Assume that the daily yield of this food is normally distributed. 9. Set up the null and alternative hypotheses to test whether the new technology has increased the mean daily yield.