In this exercise you will apply network simplex to solve the transportation problem.

$($a$)(7$ points$)$ The first step to apply $($network$)$ simplex is to find an initial basic feasible solution: This is quite easy. Specifically, first try to send as much flow as possible from outlet $1$ to Clementi. Since the supply at outlet $1$ is exhausted before the demand at Clementi is met, we fulfill the remaining demand at Clementi from the supply at outlet $2.$ Any remaining demand at outlet $2$ we then send to Queenstown and so on$.$ Follow this procedure and indicate below the basic feasible solution you get, the corresponding spanning tree, and also which are the basic arcs and the nonbasic arcs.