Which if the following statements best describes the importance of investigations in science? a. investicarion are hands on and interesting b. investigations often require testing multiple variables c. investigations often keep many people employed d. investigations can lead to discoveries that can change the world.

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

6. what does the symbol ah stand for? o one calorie given off by a reaction the specific heat of a substance the heat capacity of a substance the heat of reaction for a chemical reaction

What material does not melt at any temperature