In Fig. $12-30$ , trying to get his car out of mud, a man ties one end of a rope around the front bumper and the other end tightly
around a utility pole 18 $\mathrm{m}$ away. He then pushes sideways on the
rope at its midpoint with a force of 550 $\mathrm{N}$ , displacing the center of
the rope $0.30 \mathrm{m},$ but the car barely moves. What is the magnitude of
the force on the car from the rope? (The rope stretches somewhat.)