An object is moving in a straight line with constant acceleration a)its acceleration start increasing at some rate than b) velocity will start decreasing c) its velocity will keep on increasing d)its velocity will remain constant or objective is suddenly come to a stop

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.