The resultant of forces vector P and vector Q is vector R. If vector Q is doubled, then vector R is doubled. If the direction of vector Q is reversed, then vector R is again doubled. then P2 : Q2 : R2 is
(a) 2 : 3 : 2
(b) 1 : 2 : 3
(c) 2 : 3 : 1
(d) 3 : 1 : 1.
