For simplicity, suppose there are five students in a class. Suppose the scores of these students on three tests are as follows. Student Test 1 Test 2 82 Test 3 92 A 80 B 84 86 88 C 76 74 84 D 88 84 78 E 94 96 88 (a) Write a 5 3 matrix A to represent the information. A = (b) What are a 11, 12, and a 13? a11 = a12 a13 = == What is (11 +12 +13)? (Round your answer to one decimal place.) What does this quantity represent? O average test scores for the second test O average test scores for the first, second, and third tests student A's average test score student E's average test score O the class's average test score for all tests (c) What are a 12, a 22 a 32, 42, and a 52? a 12 = a32 = = = 842 852 What is (212 +222 +232 +242 +852)? What does this quantity represent? O average test scores for the second test O average test scores for the first, second, and third tests O student A's average test score O student E's average test score O the class's average test score for all tests