1 . Summation Summation: For the values listed below, use ( a ) the expansion method, and ( b ) the procedure outlined in Box 2 . 2 of the Nexus handout on computations ( called ' the table method ' ) to calculate the following sums: x y 5 6 3 1 7 9 2 4 a . \ Sigma x \ Sigma y b . \ Sigma x ^ 2 \ Sigma y ^ 2 c . \ Sigma ( x y ) d . \ Sigma ( x ^ 2 y ^ 2 ) e . \ Sigma ( x y ) ^ 2 f . [ \ Sigma ( x y ) ] ^ 2 Note: You must show all work for each sum. Short - cutting your work by taking advantage of the relationship between sums [ i . e . , \ Sigma x \ Sigma y = \ Sigma ( x y ) ] on this question is not permitted