An engineer in charge of a production process that produces a stain for outdoor decks has designed a study to test the research hypotheses that an additive to the stain will produce an increase in the ability of the stain to resist water absorption. The mean absorption rate of the stain without the additive is µ = 40 units. The engineer places the stain with the additive on n = 50 pieces of decking material and records y = 36.5 and s = 13.1. Determine the level of significance for testing Ha: µ = 40. Is there significant evidence in the data to support the contention that the additive has decreased the mean absorption rate of the stain using an a =.05 test?