Head lice, small insects, are found on two elementary school students. As these two students interact on the playground, some lice move from one student to the other. Which of the following is
most likely taking place in this scenario?
A-Gene flow
B-genetic drift
C-natural selection
D-nonrandom mating

How do you date a sample of rock that you suspect as being one of the earliest on earth

Radiometric dating is used to tell the absolute age of materials by studying the decay rate of radioactive isotopes. the decay rates of isotopes are constant and are expressed as .

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils