What Is the Force Acting on a Charge in an Electric Field?

[hoseA]

http://img90.imageshack.us/img90/358/electricforce8yv.png

I know how to do the first question. The second question is what's troubling me. I don't know where the forces are supposed to be directed (i.e. to which charge)... basically i don't understand what I'm finding out.

Any incite appreciated.

 

[Gokul43201]

There's a very simple relation that tells you the force acting on a charge placed in an electric field. What is it ?