Because of high production-changeover time and costs, a director of manufacturing must convince management that a proposed manufacturing method reduces costs before the new method can be implemented. The current production method operates with a mean cost of $220 per hour. A research study will measure the cost of the new method over a sample production period. (a) Develop the null and alternative hypotheses most appropriate for this study. H0: μ - Select your answer - $ Ha: μ - Select your answer - $ (b) Comment on the conclusion when H0 cannot be rejected. When H0 cannot be rejected, there - Select your answer - enough evidence to conclude that the proposed manufacturing method - Select your answer - costs. (c) Comment on the conclusion when H0 can be rejected. When H0 can be rejected, there - Select your answer - enough evidence to conclude that the proposed manufacturing method - Select your answer - costs.