Question: Answer the following question given this paragraph: A change of state occurs whenever matter changes from one state to another. Changes of state are physical changes in matter. They are reversible changes that do not change matter's chemical makeup or chemical properties. Q: What do you call reversible changes that do not change matter's chemical makeup or chemical properties? Choices: - potential changes - element changes - chemical changes - physical changes A:
Answer: physical changes

Question: Answer the following question given this paragraph: Alpha particles can travel only a few centimeters through air. They can burn the skin but not penetrate it. Beta particles can travel up to a meter through air. They can penetrate and damage skin. Gamma rays can travel thousands of meters through air. They can penetrate and damage cells deep inside the body. Q: What kind of rays can travel thousands of meters through air and can penetrate and damage cells deep inside the body? Choices: - x-rays - cosmic rays - plasma rays - gamma rays A:
Answer: gamma rays

Question: Answer the following question given this paragraph: Ion drives have low thrust but high efficiency. They have already been used on several space missions, including NASA's Deep Space 1spacecraft and Japan'sHayabusa asteroid sampling probe. Source: Photo courtesy of NASA,http://commons. wikimedia. org/wiki/File:Ion_Engine_Test_Firing_-_GPN2000-000482. Q: Ion drives have low thrust but high what? Choices: - power - acceleration - tolerance - efficiency A:
Answer:
efficiency