Answer
We can rank the forces according to the magnitudes of the torques they create about point $P_3$:
$F_1 = F_3 \gt F_2$
Work Step by Step
We can write a general expression for the magnitude of the torque:
$\tau = r ~F~sin~\phi$
We can find an expression for the magnitude of the torque about point $P_3$ that is created by each force:
Force 1:
$\tau_1 = (r)(F)~sin~90^{\circ} = r~F$
Force 2:
$\tau_3 = (r)(F)~sin~\phi =r~F~sin~\phi$
Note that: $~~0 \lt sin~\phi \lt 1~~$ since $~~90^{\circ} \lt \phi \lt 180^{\circ}$
Force 3:
$\tau_1 = (r)(F)~sin~90^{\circ} = r~F$
We can rank the forces according to the magnitudes of the torques they create about point $P_3$:
$F_1 = F_3 \gt F_2$
