The production control manager at Ashmore Manufacturing is interested in determining whether there is a difference in standard deviation of product diameter for a part for units made at the Trenton, New Jersey, plant versus those made at the Atlanta plant. The Trenton plant is highly automated and thought to provide better quality control. Thus, the parts produced there should be less variable than those made in Atlanta. A random sample of 15 parts was selected from those produced last week at Trenton. The standard deviation for these parts was 0.14 inch. A sample of 13 parts was selected from those made in Atlanta. The sample standard deviation for these parts was 0.252 inch. Based on these sample data, what is the conclusion if they want to see whether the Trenton plant produces parts that are less variable than those of the Atlanta plant? Test using a = 0.05. O a. non of them O b. d not reject Ho c. The is sufficient evidence to accept HA d. The is no sufficient evidence to reject Ho