At birth, males and females are distinguished by which are the genitals, organs used for reproduction.

How can scientists test their ideas about the origin of the universe if they can't physically interact with or study?

The earth's oceans are made up of chlorine, and trace elements. a) carbon, oxygen b) oxygen, silicon c) hydrogen, oxygen d) nitrogen, oxygen

Energy stored in the bonds that hold together the atoms and molecules of all substances is called a. kinetic energy. b. electrical energy. c. mechanical energy. d. chemical energy.