Is earth made mostly gas or rock

Exactly what kind of weather conditions would a cold front produce?

Some gamma ray bursts are hypothesized to come from mergers of neutron stars or black holes. if this hypothesis is correct, what else should we in principle be able to detect from such mergers? a. gravitiational waves b. x-ray bursts c. significant disruption of gas thousands of light-years away in the surrounding galaxy d. an "afterglow" of bright visible light, lasting for weeks

What is one difference between austria and switzerland? a. austria is landlocked. b. austria has more minerals resources c. austria has a strong tourism industry d. austria has a strong dairy cattle industry