1. Out of 100 numbers, 20 were 4's, 40 were 5's, 30 were 6's and the remainder were 7's. Find the arithmetic mean and median of the numbers. 2. A student's final grades in FD12A, GT24M, EC16A and EC14C are, respectively, 82, 86, 90, and 70. If the respective credits received for these courses are 0, 6, 3, and 3, determine an appropriate average grade. Use the raw data from Task I to compute a 10% trimmed mean.