Test a claim that the mean amount of carbon monoxide in the air in U.S. cities is less than 2.31 parts per million. It was found that the mean amount of carbon monoxide in the air for the random sample of 66 cities is 2.41 parts per million and the standard deviation is 2.09 parts per million. At a = 0.10, can the claim be supported? Complete parts (a) through (e) below. Assume the population is normally distributed. www (c) Find the standardized test statistic, t. The standardized test statistic is t = 0.389 (Round to two decimal places as needed.) (d) Decide whether to reject or fail to reject the null hypothesis. Fail to reject Ho because the standardized test statistic (e) Interpret the decision in the context of the original claim. There is not enough evidence at the carbon monoxide in the air in U.S. cities is (Type integers or decimals. Do not round.) in the rejection region. level of significance to less than the claim that the mean amount of 2.31 parts per million.