It's been estimated by the national health authority of Mexico that on average the Mexican adults drink 18 cans of Coca-Cola a week which causes a drastic increase in diabetes and high blood pressure among them. A recent survey conducted by an NGO indicates that on average the daily consumption of Coca-Cola by a Mexican adult is 2.7 with a total standard deviation of 3.3 cans and 60 degrees of freedom.

1. Using a 97.5% confidence level and P-value approach can you conclude that the Mexican adult's average weekly consumption of Coca-Cola is more than 18 cans?
2. Determine a 97.5% confidence interval for the corresponding population mean.