4)general sol: (dv/dt)=(4(v^2)+36)(t^2)
There are people on MHF who are trying to offer *help* (that's what the "H" stands for in MHF). If you want help, I don't think it's unreasonable that you be asked to show some work. Furthermore, this most recent post is very off-putting. It may be that English isn't your native language, but you might still try to clean it up a bit!
Finally, here's a site that will help you format your questions in a pretty way. Online LaTeX Equation Editor - create, integrate and download
Now, #4 looks like it's "separable"
Can you integrate both sides? A trig substitution might help on the left...