Metamorphic rocks result from the A) cooling and solidification of molten magma
B) compression and cementation of soil particles
C) recrystallization of rocks
D) erosion of rocks​

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Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

Estimate the molar mass of the gas that effuses at 1.6 times the effusion rate of carbon dioxide.