How many nonzero elements are in the matrix? the 5 by 6 matrix, row 1, column 1, 2 column 2, 0 column 3, 0 column 4, 3 point 1 column 5, 22 column 6, 9 row 2, column 1, 0 column 2, 21 column 3, 3 point 2 column 4, 0 column 5, 0 column 6, 6 row 3, column 1, 1 column 2, 42 column 3, 0 column 4, 0 column 5, 0 column 6, 8 row 4, column 1, 40 column 2, 0 column 3, 0 column 4, 4 column 5, 6 column 6, 14 row 5, column 1, 10 column 2, 20 column 3, 0 column 4, 13 column 5, 5 column 6, 6 point 3