Perform one row operation R2←R2−2R1R_2 \leftarrow R_2 - 2R_1R2←R2−2R1 on the matrix A=(1327)A = \begin{pmatrix} 1 & 3 \\ 2 & 7 \end{pmatrix}A=(1237). What is the new second row?
[0,1][0, 1][0,1]
[0,−1][0, -1][0,−1]
[2,1][2, 1][2,1]
[1,1][1, 1][1,1]