What is the magnitude of the moment done by the force about point "O" in the following figure. Hint: Determine the moment of the force 'F' in Cartesian vector form then deduce the magnitude:
F = |9i - 12j - 20k| N
Select one:
a. 510 N.m
b. 260 N.m
c. 600 N.m
d. 180 N.m