Question: 3.1. The production of a nationally marketed detergent results in certain workers receiving prolonged exposures to a Bacillus subtilis enzyme. Nineteen workers were tested to determine the effects of those exposures, if any, on various respiratory functions. One such function, air-flow rate, is measured by computing the ratio of a person's forced expiratory volume (FEVI ) to his or her vital capacity (VC). (Vital capacity is the maximum volume of air a person can exhale after taking as deep a breath as possible; FEVI is the maximum volume of air a person can exhale in one second.) In persons with no lung dysfunction, the "norm" for FEV1IVC ratios is 0.80. Based on the following data (169), is it believable that exposure to the Bacillus subtilis enzyme has no effect on the FEV1/VC ratio? Answer the question by constructing a 95% confidence interval. Assume that FEVI/VC ratios are normally distributed with \(\sigma \) = 0.09.