True or False; Most moons in the solar system have compositions of rocky and metallic cores with crusts of ices. True or False; Life on Earth has had a negligible impact on the atmosphere until very recently. True or False; Geological activity, such as volcanism, is unique to Earth in our solar system. True or False; The darker lava plains on the Moon are older than the lighter heavily cratered highlands. True or False; The process by which the interiors of planets are divided into multiple layers of variable density is called diffusion. True or False; In the past century of increased industrial and agricultural development, the amount of CO 2
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in the atmosphere increased by about 30%. True or False; Mercury is the densest planet.