1) at highest point V = 0
so 0 = Vo - gt
=> t = Vo / g = 26.8 / 9.81 = 2.73 s <<<<<<<<,
2) find its highest point :
V^2 = Vo^2 - 2gh
hence h = Vo^2 / 2g = 36.6 m from its starting point
so total height = 36.6 + 2.1 = 38.7 m
applying h = Vot + 1/2 g t^2 u get :
38.7 = 0 + 1/2 (9.81) t^2
=> t = 2.8 s <<<<<<<<<