The position-time equation for a certain train is xf = 2.6m + (8.9m/s)7 + (2.5m/s^2)t^2 What is the initial velocity of this train and the acceleration?

Iron reacts with sulfur to form iron sulfide. if 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

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? ?

Ineed the answer to question 1 , i’m desperate