Convection causes large masses of rock to rise from and sink into Earth's mantel. The main heat source for this movement is 1.Earth's maritle and core.
2.Friction produced by plate motions.
3.Radiation from the sun
4.Magma in Earth's crust.

St. louis, missouri, and san francisco, california, both lie around 33° north latitude. st. louis is inland, while san francisco is on the coast of the pacific ocean. which statement about these north american cities would be true? san francisco will be warmer than st. louis in the winter. san francisco and st. louis will be about the same temperature year round. san francisco will be warmer than st. louis in the summer. san francisco will be warmer than st. louis year round.