A particle moves along a line so that its position at any time is t>0 or t=0 is given by the function s (t) = (t^3) - (6t^2) + (8t) + 2 where s is measured in meters and t is measured in seconds. a) find instantaneous velocity at any time t. b) find acceleration of the particle at any time t. c) when is the particle at rest?. d) describe motion of the particle. at what values of t does the particle change directions