The plates of the earth's crust may also contribute to maintaining upper mantle convection. true false

That is very true

The uppermost mantle is connected to the crust and forms the asthenosphere, which composes Earth's tectonic plates. The bulk of the mantle is composed of extremely hot rock under enormous pressure. The mantle may be very close to the melting point of the rock which composes it, or even partially melted. Mantle rock is higher in magnesium and iron than the crust. Rocks in the upper mantle are composed of the minerals olvine, garnet, spinel and pyroxene. With increasing depth, some of these minerals become unstable and are replaced by mineral polymorphs which have the same chemical composition, but different structures. For more information on the composition of the mantle as a whole.

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it