Substance a contains 75% carbon and 25% hydrogen. substance b contains 80% carbon and 20% hydrogen. a and b are the same substance. a. true b. false

Rocks, as they are compressed, begin forming mountains above the earth's surface when two continental plates converge. the continental crust increases in depth as the mountains grow above. the himalayan mountains formed at a convergent plate boundary in this manner. the rocks are smashed together causing them to due to the intense heat and pressure from the colliding plates and eventually forming rock. a) melt; igneous b) layer; sedimentary c) recrystallize; metamorphic d) melt into the earth's interior; metamorphic

What must occur for air masses to form fronts

The picture represents the process that produces most of the energy used by living organisms on earth. which process is represented in the picture? a) the magnetic attraction between two hydrogen nuclei. b) the fusion of hydrogen nuclei to produce a helium nucleus in the core of the sun. c) the fission of hydrogen nuclei to produce a helium nucleus in the core of the sun. d) the chemical reaction between hydrogen nuclei to produce a helium nucleus in earth's atmosphere.