A random sample of 20 recent weddings in a country yielded a mean wedding cost of $26,364.94. Assume that recent wedding costs in this country are normally distributed with a standard deviation of $7900. Complete parts (a) through (c) below. a. Determine a 95% confidence interval for the mean cost, u, of all recent weddings in this country. The 95% confidence interval is from $ to $. (Round to the nearest cent as needed.)