Completely lost in Statics and this is literally the second homework

[kenna]

Homework Statement

I need help with questions 3 5 and 6 I managed to figure out the other three but I don't even know where to begin with these.

Relevant Equations

I know I need moment but that about it

For problem 3 I managed to get the angles between AB and BC and divided by 2 it ends up being 18.43. The angle between AD and the axis is 33.69 but I'm not sure what to do after that point. I have going from A to that cross as the Z axis and then y going up and x going parallel to the box.

 

[Lnewqban]

Welcome!
We need you to show your best attempt.
Could you do free body diagrams for those problems?