A copper smelting process is supposed to reduce the arsenic content of the copper to less than 1000 ppm. Let μ denote the mean arsenic content for copper treated by this process, and assume that the standard deviation of arsenic content is σ = 140 ppm. The sample mean arsenic content X¯¯¯ of 95 copper specimens will be computed, and the null hypothesis H0: μ ≥ 1030 will be tested against the alternate H1: μ < 1030. A decision is made to reject H0 if X¯¯¯≤ 1010. Find the power of the test if the true mean content is 985 ppm. Round the answer to four decimal places.

The power is