How Is Total Work Calculated for Two Connected Blocks with Friction?

[james brug]

Homework Statement

Two blocks are connected by a very light string passing over a massless and frictionless pulley . The 20.0 N block moves 75.0 cm to the right and the 12.0 N block moves 75.0 cm downward.

Find the total work done on the 20 N block if $$\mu _s\;$$=(coeff. of static friction)=0.500 and $$\mu _k \;\;\;\;$$=(coeff. of kinetic friction)=0.325 between the table and the 20 N block.

Homework Equations

$$w=f\cdot d$$
$$f_k=\mu_k\cdot n$$
$$f_s\leq\mu_s\cdot n$$

The Attempt at a Solution

w=[7.5N-(.325)(20N)](.75m)=.75J--wrong.

 

[james brug]

Never mind. I've solved it myself through some careful research and considerable effort. It is unfortunate that no one was able to answer this in time. Perhaps you people want some monetary compensation? Or maybe no one liked my problem. Not particularly hard, is it?