Car turning at 20 m radius with pendulum deflecting 37 degrees

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A car takes a turn, radius = 20 m. Meanwhile a pendulum inside the car shifts 37 degree. Find the velocity of the car and find all the forces acting on the pendulum.

How to solve this? It doesn't mention from what position the pendulum starts...
 
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Assume the pendulum is a bob on the end of a string.
The bob is moving in a circle of radius r = 20m.

What are the forces acting on the bob ?
 
I forgot to mention that the length of the string is 0.10 m... I'm affraid you got me lost...
 
You don't actually need the length of the string to answer your problem about the car's velocity.

There are only two forces acting on the bob, the weight of the bob itself, and the tension in the string.
The bob is supported vertically and the bob is moving in a circle so must have a centripetal acceleration. How does the tension in the string provide both (vertical) support for the bob and centripetal acceleration/force on the bob ?

Edit: the bob isn't supported vertically. That implies the string is straight up and down. The string is only vertical if the bob is moving in a straight line at constant velocity. Since it is moving in a circle, its inertia will tend to make it swing outwards from the vertical and away from the centre of rotation. BTW, this is a problem on centripetal force/acceleration.
 
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Actually I think in relationship with a passenger, I think only gravity and the tension of the string acts on the pendulum. This is like comparing the Earth and a person. Well thinking of I think the question it pretty awkward. Maybe the real meaning is that the car shifts 37 degree and I only need to find the period to determine to velocity of the car. Does this seems right or not?
 
Do you know how to add two Force vectors? That's what you have ...

Why do you think we might want to add them?