Which of the following are true: 1 Melting is a reversible change. 2 Decomposition is a reversible change. 3 Decomposition is a chemical change

How much work is done lifting a 9.10 kg box straight up onto a shelf that is 1.80 m high?

Aproton is projected toward a fixed nucleus of charge +ze with velocity vo. initially the two particles are very far apart. when the proton is a distance r from the nucleus its velocity has decreased to 1/2vo. how far from the nucleus will the proton be when its velocity has dropped to 1/4vo?

Which branches of natural science include the study of an organism that lived 10 million years ago