The observed bearings of a traverse are given below:

$\begin{array}{|c|c|c|c|c|} \hline \text{Line} & \text{Bearing} & {} & \text{Line} & \text{Bearing} \\ \hline PQ & 46^{\circ} 15’ & {} & QP & 226^{\circ} 15’ \\ \hline QR & 108^{\circ} 15’ & {} & RQ & 286^{\circ} 15’ \\ \hline RS & 201^{\circ} 30’ & {} & SR & 20^{\circ} 30’ \\ \hline ST & 321^{\circ} 45’ & {} & TS & 141^{\circ} 45’ \\ \hline \end{array}$

The station(s) most likely to be affected by the local attraction is/are

1. Only $R$
2. Only $S$
3. $R$ and $S$
4. $P$ and $Q$