What are the different isotopes

James is trying to prove newton's 2nd law of motion. he tries to move four different objects with different masses, shapes, and sizes from point a to point b. the objects are a toy car, a car, a refrigerator, and a kitchen table. after some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. the object that takes the most force to move is the

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

The substances that are necessary for producing of certain hormones and that store and transport vitamins