When materials are moving across a membrane

Idon’t know the answer and i’ve been stuck on it for a while now skskskskks

Why is earth's outer core hotter than earth’s oceanic crust? earth’s oceanic crust is denser than earth’s outer core is. earth’s oceanic crust has lava flowing from the mantle. earth’s outer core has a composition of solid iron and nickel. earth’s outer core is deeper within earth than oceanic crust is.

Explain why it’s important for scientists to study the sun. list at least two challenges researchers face when examining earth’s nearest star.