distance scale

force scale

mass scale

time scale

zero

1

2

infinity

one specified point

two specified points

three specified points

more than three specified points

be in equilibrium

always reduce to a resultant force

always reduce to a couple

both (a) and (c)

that polygon of forces must close

that resultant couple must be zero

both that polygon of forces must close and that resultant couple must be zero

none of the above