The begging is not needed and offensive.
You have had some input on question 16 in another thread, so I'll give you an idea of where to start and you can let us know how you did with it.
As in Q16 set up a Free-Body-Diagram (or a force diagram, whatever your instructor may call it.) What you are looking for is a tension in the wire such that m2 has no acceleration on it. That means that m1 has no acceleration either. So set a = 0 in your equations and see what comes up.
-Dan
I would suggest that you use energy principles: $\displaystyle \Delta KE + \Delta PE = 0$. The kinetic energy of the system is $\displaystyle \frac 1 2 (m_1+m_2)v^2$. The change in potential energy for each mass is equal to mg times the height it rises (note that for m2 since it is moving downhill it's change in PE is negative). So all you need do is come up with an expression for the height rise of each mass, set up the energy equation, and solve for v. Show us your attempt and we'll give more advice if you need it.