Multiple Pullys and determing Tension

[e4canadian]

Multiple Pulleys and determing Tension Dynamics

So i started out with the the equation for the tension of the block-pulley system on the far left in the y direction being: 2T-2g = 2*a1
the equation for the middle block-pulley system is: 2T-2g = 3*a2
the equation for the block on the ramp is: T - 20*9.8*sin60 = 20a3

I need an equation to relate the three accelerations using conservation of string but i do not know how to write it.

 

[e4canadian]

I am studying for a midterm and this is a question from a previous years midterm the answer is d, but i do not know how to get it.