Prove that U, W are subspaces of M2x2(R). Find at least one spanning set for U and at least one for W. Determine at least one subspace of M2x2(R) that

contains both U, W as well as at least one that is contained in both U, W. \mathbb{U}=\left\{\left[\begin{array}{ll} a & b \\ c & d \end{array}\right]: a_{4} a-a_{6} d=0\right\} \mathbb{W}=\left\{\left[\begin{array}{ll} a & b \\ c & d \end{array}\right]:\left[\begin{array}{ll} a_{8} & 0 \end{array}\right]\left[\begin{array}{ll} a & b \\ c & d \end{array}\right]=\left[\begin{array}{ll} 0 & 0 \end{array}\right]\right\}