So fustrated and need some desperate help

[HighVoltage]

all,
i am stuck on this problem. physics has not been good to me this semester. its like "in one ear out the other"

this is the problem:

i can't get c or d.

for c i tried .25(29*9.8+117.37*sine(40)) that wasnt right

for d i tried 117.37*4.1 and that wasnt right

please help me.

 

[learningphysics]

For part c), you forgot to multiply by the distance... also the work by friction is negative...

Think about this... the crate is moved at constant velocity... so what is the net work done on it by all forces? (what does the work energy theorem say?)