http://physicsed.buffalostate.edu/courses/software/modeling/1st_mechanics/PDF%20files/4-FP-Inertia/Tests/Quiz%201.pdf
1) I don't know how to do this, but I know there is the force of gravity by the Earth in the force diagram..
2) For this one I got the answer
Fx=7.5N [I did 1/2(15N) which...