How Much Force Is Required to Pull a Platform at an Angle?

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Homework Statement


A 33.5 kg person stands on a 67 kg platform.
He pulls on the rope that is attached to the
platform via the frictionless lower-right pul-
ley. He pulls the rope at an angle of 35◦ to the
horizontal, as shown in the figure below.
Assume: g = 9.8 m/s2 . Ignore friction.
The platform remains level.
[PLAIN]http://img201.imageshack.us/img201/5122/010011.png

(a) If he pulls the platform up at a steady rate,
how much force is he pulling on the rope?

(b)In Part 1 we assumed that the platform re-
mains level. This is a bad assumption.
However, if the man were pulling straight
up on the rope, the forces will be balanced
and the platform should remain level.
1. This is a good assumption.
2. Cannot be determined.
3. This also is a bad assumption.

Homework Equations


Sum of Fy= T-Mg=0=> Mg=N, where M=m1+m2
Sum of Fy= N-Mg+Fsintheta=Ma
Sum of Fx=Fcostheta=0


The Attempt at a Solution


So I know T7=T6, does T7 also equal T2?
Does T5= T7+T6?
Does T3=T1+T2?

What equation can I use to calculate T1?
 
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What are T5 and T3 supposed to be? The tension where the pulleys are fixed to the ceiling?

Anyway, frictionless pulleys will not change the tension at any point in the single rope. So T1, T2, T4, T6, and T7 are all equal. But when examining net forces, you look at each of these "Ts" when finding the net force on an object. So haw many of these tensions are supporting the platform?How many of these te