5th Graders ACE This Test. . . Can YOU!? Which of the following is a primary source of energy for the human body? Protein Carbohydrates Fats Vitamins None What is the largest ocean on Earth? Indian Ocean Atlantic Ocean Pacific Ocean Arctic Ocean None Which two gasses make up the majority of Earth's atmosphere? Oxygen and nitrogen Oxygen and carbon dioxide Nitrogen and carbon dioxide Nitrogen and helium None What is the largest organ in the human body? Heart Brain Liver Skin None Which planet is known as the "Red Planet"? Venus Mars Jupiter Saturn None Time's up Most Popular Most Popular
