Please help me with this!!

Which statement about sound is not true? a. air particles travel with sound waves. b. sound waves cannot travel through a vacuum. c. sound waves exist even if no one hears them. d. air particles vibrate along the path of a sound wave.

Water is important for the of cells. a: size, shape, and temperature b: temperature, color, and odor c: color, odor, and size d: shape, temperature, and color

Nonpoint source pollution is difficult to control because it