A robotics scientist is trying to create a baseball pitching machine that will throw balls at different speeds and in exactly the same location every pitch. They have put a magnet in the baseball and behind home plate. Explain to the scientist two reasons why some objects experience more kinetic energy than others?

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium