A disc is rotating with angular velocity `omega`. A force `F` acts at a point whose position vector with respect to the axis of rotation is `r`. The power associated with torque due to the force is given by
Options:
(a) `(r xx F)•omega`
(b) `(r xx F) xx omega`
(c) `r xx (F•omega)`
(d) `r•(F xx omega)`