1
Speed Grid (+): Fill in each cell by applying the operation to the row and column headers. Row headers: [8, 1, 8, 5], Column headers: [9, 10, 9, 1] =
2
Speed Grid (-): Fill in each cell by applying the operation to the row and column headers. Row headers: [3, 2, 3, 6], Column headers: [5, 2, 5, 9] =