Short Answer

$$\text { Find the transitive closure of } R \text { if } \mathbf { M } _ { R } \text { is } \left( \begin{array} { l l l l } 1 & 0 & 1 & 0 \\1 & 0 & 0 & 1 \\0 & 1 & 1 & 0 \\0 & 1 & 0 & 0\end{array} \right) \text {. }$$