For the truss shown in figure, the magnitude of the force

For the truss shown in figure, the magnitude of the force in member PR and the support reaction at R are respectively

1. 122.47 kN and 50 kN
2. 70.71 kN and 100 kN
3. 70.71 kN and 50 kN
4. 81.65 kN and100 kN

∑M_Q = 0
100 × cos 60° × 4 = R_a × 4
⇒ R_a = 50 kN
F_PR × cos 45° = 100 cos 60°
⇒ F_PR = 70.71 kN