A convecting mantle is an essential feature of plate tectonics and contributes to the formation of both igneous and metamorphic rocks. Where does the thermal energy that drives these convection currents come from? A)The convection of the mantle is driven by the heat gradient within the mantle layer itself.
B)The convection of the mantle is a product of the transfer of heat from the core to the lower mantle.
C)The convection of the mantle is the result of the radioactive decay of nickel occurring within the core.
D)The heat is the frictional heat from the rotating fluids within the core of the Earth which rises up into the mantle.

Atrain departs from its station at a constant acceleration of 5 m/s. what is the speed of the train at the end of 20s?

Atelevision set that has been running for a while heats up even the air around it. which two laws of thermodynamics could be used to analyze this scenario

Your starship, the aimless wanderer, lands on the mysterious planet mongo. as chief scientist-engineer, you make the following measurements: a 2.50-kg stone thrown upward from the ground at 14.0 m/s returns to the ground in 5.70 s ; the circumference of mongo at the equator is 2.20×10^5 km ; and there is no appreciable atmosphere on mongo. (a) the starship commander, captain confusion, asks for the following information: what is the mass of mongo? (b) if the aimless wanderer goes into a circular orbit 2.20×10^4 km above the surface of mongo, how many hours will it take the ship to complete one orbit? (c) an unmanned spacecraft is in a circular orbit around the moon, observing the lunar surface from an altitude of 44.0 km . to the dismay of scientists on earth, an electrical fault causes an on-board thruster to fire, decreasing the speed of the spacecraft by 23.0 m/s . if nothing is done to correct its orbit, with what speed (in km/h) will the spacecraft crash into the lunar surface?