The correct answer is option A.) "joints; cooling and contracting during formation".
Explanation:
In Geology, a joint is a break or fracture that is naturally formed within a rock. Joints are formed as a result of cooling and contracting during its formation, or by the addition of layers of minerals during its formation.The rocks will break along their joints when they are hit with hammers because joints are their weak spots.
science is different from many other ways of learning because of the way it is done. Science relies on testing ideas with evidence gathered from the natural world.
Any atom at the ground state has its orbital levels fill from the bottom (close to the nucleus) – up. The inner orbitals are of lower energy state and fill first because the atoms ‘likes’ to exist in the low energy and more stable state. Only when the atom is in an excited state do some of the electrons in the lower orbital levels shift to higher unfilled orbitals.
