GA Q10

A plot of land must be divided between four families. They want their individual plots to be similar in shape, not necessarily equal in area. The land has equally spaced poles, marked as dots in the below figure. Two ropes, $\text{R1}$ and $\text{R2},$ are already present and cannot be moved. What is the least number of $\textsf{additional}$ straight ropes needed to create the desired plots? A single rope can pass through three poles that are aligned in a straight line.