Which of the following is true of the Celsius scale? a. 212 degrees is the boiling point of water. b. 0 degrees is absolute zero. c. 0 degrees is the freezing point of water. d. 32 degrees is the freezing point of water. Please select the best answer from the choices provided A B C D

Why are biogeochemical cycles important? earth is a closed system. that means the amount of rocks, metals, carbon, nitrogen, oxygen, and water on so, it is essential that biogeochemical these materials as they move through earth's subsystems.

Asap and show ! a 14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?