Physics Lab Help

Question

I did a lab in physics and I can't figure out how to find the coefficient of friction. Here are the lab rules - 

Allowed measurements =

M₁, M₂, d, h, ∆t₂

No ∆t₁

Can use Work Energy Ideas and Kinematics.

CANNOT USE F = MA

There is friction between M₁ and the table, the pulley is frictionless and there is no air resistance. I need help using the work energy theorem with this to find the coefficient of friction...

This is the equation we were given - W_{Friction of M1} + W_{Normal Force of M2} = Total energy

 

I drew a picture of what happened during the lab and what the measurements are. 

Here is my data - 

Mass of M₁ - .1284 Kg

Mass of M₂ - .055 Kg

d = 1.11 m 

h = .81 m

∆t₂ = 1.00s 

I tried to do the calculation myself and I got μ = .56389, I just don't think it is right.

Sorry for the long windedness... thank you for your help!!!