An object cannot remain at rest unless which of the following holds? there are no forces at all exerted on it. there is only one force exerted on it. the net force exerted on it is constant and nonzero. the net force exerted on it is zero. if a block is moving to the left at a constant velocity, what can one conclude? the net force exerted on the block is directed to the left. the net force exerted on the block is zero. there must be no forces at all exerted on the block. there is exactly one force exerted on the block. a block of mass 2kg experiences a force of magnitude 4 newtons directed to the right. what can you say about the block's motion? it must be moving to the left. it could be moving to the left, moving to the right, or be instantaneously at rest. it must be moving to the right. it must be at rest. a block is being pulled along a horizontal frictionless surface by a constant horizontal force. the block must be moving with a constant nonzero acceleration. moving at constant velocity. moving with continuously increasing acceleration. continuously changing direction.