A pendulum bob at its highest point has a certain amount of potential energy. As it falls, what does the potential energy get transformed into? A. kinetic energy only B. potential energy only C. kinetic energy and heat energy D. potential energy and heat energy

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal.b. he is determining chemical properties that are sufficient to identify the metal.c. he is determining physical properties that are insufficient to identify the metal.d. he is determining chemical properties that are insufficient to identify the metal.

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?