An object of mass 1 kg is launched with an initial speed of v_o into a large tank filled with a viscous liquid. The liquid exerts a resistive force (drag) of the form D = αv on any object that is moving inside it, where v is the instantaneous speed of the object and α = 1 kg/s. If the effect of gravity is ignored, the time taken by the object to slow down to the speed v_o/2 is ________ s (rounded off to 2 decimal places).
Assume that the tank is sufficiently large for the above deceleration to happen inside the tank.