[b]A particle moves along a straight line. Its displacement, s metres from the fixed point O time t is given by at time t is given by [/b][math]s=2t^3-5t^2+4t[/math][b]. Find[br][br]a) the instantaneous velocity, in [/b][math]ms^{-1}[/math][b], of the particle when t=2,[/b]

[b]b) the values of t, in seconds, when the particle stops instantaneously,[/b][br]

[b]c) the range of values of t, in seconds, when the car moves to the right.[/b]