Ascientist uses materials in her lab to turn one piece of dna into 100 copies

The main ingredient of magma is a pahoehoe. b silca c dissolved gases d obsidian

Pulmonary arteries carry highly oxygenated blood. true or false?

Aragonite shells of clams, snails, or scleractinian corals may be preserved unaltered in cenozoic deposits, but they are generally dissolved or recrystallized in older deposits. true or false