Why are rocks made of lime stone usually an indication that an area was previously covered by ocean water

What is the farthest destination to date for a human spaceflight mission?

Hydrogen has only one electron in its only (and outer) electron shell. if a hydrogen atom were to absorb a small amount of energy, where would bohr say the electron would go? a. fly off the atom b. nowhere, it would just speed up. c. spiral inwards towards the nucleus d. move up to another shell that would form

Under capitalism, the allocation of goods and services is determined by consumers. the government. businesses. free market forces.