The appropriate answer is a. the temperature is high enough but pressure low enough to melt iron. The earth's core is composed of two layers; the inner and outer core. Both layers are composed mainly of iron and nickel. The main difference between the two layers is that the inner core is solid and the outer core is liquid. The inner core is solid because of the pressure created by the overlaying layers; the outer core, mantle and the crust. The inner core is however hotter than the outer core.
They export from the United States.
According to one hypothesis, life on earth emerged from (bluegreen algae/ amino acids/ molten metals/ crustal rocks) in the presence of large amounts of gasses seeping from deep ocean vents. ANother process called primordial soup suggests that the formation of life was due to the effects of (lightning/sunlight/gravity/meteorites) in earths atmosphere.
D. They do not produce electricity.
Passive solar heating is a technique where the sun's energy
is used for heating spaces. It does not generate electricity but can save substantial
electricity by making use of thermal mass. Materials that have a high density
such as concrete and bricks absorb and store electricity. Along with operable windows
and thermal chimneys, thermal mass is being
utilized to take advantage of sun exposure.
