magnitude

direction

position or line of action

all of these

not a replace them by a single force

to replace them by a single force

to replace them by a single force through C.G.

to replace them by a couple

magnitude

direction

point of application

all of these

P/2 cos 9/2

IP sin 9/2

2P tan 9/2

IP cos 9/2

forces

independence of forces

dependence of forces

resolution of forces.