a child runs 60m race with an average speed of 4 m/s. how long did the child take to complete the race? give the correct unit for your answer plz

As a part of an experiment a student burns propane to produce carbon dioxide and water she remembers that she must follow the law conservation of matter when writing a balanced chemical equation which of these equation adheres to the law of conservation of matter

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

In 2002, the rare earth elements mine in mountain pass, california was closed because