An ant is dragging a house-fly and the elephant is pushing a big tree which is not moving. who is doing work, the ant or the elephant? justify your answer​

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?

What is the measurement of how fast an object moves relative to a reference point?

Consider the following position function. find (a) the velocity and the speed of the object and (b) the acceleration of the object. bold r left parenthesis t right parenthesisr(t)equals=left angle 6 t superscript 4 baseline comma 2 t cubed right angle6t4,2t3 for tgreater than or equals≥0