How is the oceanic crust different from the continental crust

answer: the oceanic crust is denser than the continental crust

explanation:

the mantle, oceanic crust and continental crust have different densities because they are made of different kinds of rock with different densities. the continental crust is made mostly of rocks with a composition similar to granite (a light-colored rock you would expect to find in the sierra nevada), whereas the oceanic crust is made mostly of rocks with a composition of basalt (a dark- colored rock, like the rocks that make up the hawaiian volcanoes).

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).