Answer the following question given this paragraph: Fission is the process in which an atomic nucleus breaks apart into two less massive nuclei. Energy is released in the process in many forms, heat, gamma rays and the kinetic energy of neutrons. If these neutrons collide with nuclei and induce more fission, then a runaway chain reaction can take place. Fission is responsible for nuclear energy and atom-bomb explosions: the fission of uranium acts as a heat source for the Earth's molten interior. Q: The process where an atomic nucleus breaks apart into two less massive nuclei is known as ______. Choices: - diffusion - fusion - collision - fission A:
fission

Answer the following question given this paragraph: The rate of decay of a radioactive substance is constant over time. Q: What remains a constant of radioactive substance over time? Choices: - temperature - volatility - acidity - rate of decay A:
rate of decay

Answer the following question given this paragraph: Coal has different grades. Bituminous coal forms at lower temperatures. It contains a lot of sulfur. When it is burned, it causes a lot of pollution. Anthracite coal forms under higher temperatures. This drives off the sulfur, and the coal burns more cleanly. Q: What type of coal is formed at lower temperatures? Choices: - clean - calcareous - limestones - bituminous A:
bituminous

Answer the following question given this paragraph: The lithosphere-asthensophere divisions are based on mechanical properties. Q: The lithosphere-asthensophere divisions are based on what? Choices: - mechanical compounds - elemental properties - constant properties - mechanical properties A:
mechanical properties