Quarters are currently minted with weights normally distributed and having a standard deviation of 0.067. New equipment is being tested in an attempt to improve quality by reducing variation. A simple random sample of 27 quarters is obtained from those manufactured with the new equipment, and this sample has a standard deviation of 0.044. Use a 0.05 significance level to test the claim that quarters manufactured with the new equipment have weights with a standard deviation less than 0.067. Does the new equipment appear to be effective in reducing the variation of weights? (a) Write the claim mathematically and identify Ho and Ha. OA. Ho: 0.067 (Claim); Ha: 0.067 (Claim) (b) Find the critical value(s). (Use a comma to separate answers as needed. Round to three decimal places as needed.)