Expert Mechanics Help: Solving Moment of Force Problems | 6 Unsolved Issues

[bookworms]

this is about moment of a force ...
acctually this is 10 problems i already solve the 4
but i can't solve this 6 problem

some of the problems already have a correct answer...

thanks a bunch...

 

[bookworms]

Additional details
NOTE:
This is not my homework i just want to see what is the solution of the ff problems
because I am reviewing for my exam next week ... thanks for all the help ^^

 

[bookworms]

this are the answers LOL ...