Early european monarchs sought the support of the middle class because
a) the middle class was increasingly the source of tax revenue.
b) the middle class was the largest social class in each country.
c) peasants outnumbered the nobles and were a constant threat to rebel.
d) international trade was decreasing because of the actions of peasants.

Some organisms have a large geographic range. for example, the norway rat lives on every continent except antarctica. a population of norway rats is the number of rats in one particular area. do you think it’s scientifically possible for a population of norway rats in north america to carry different genetic mutations than a population of norway rats in africa? do you think it’s possible that they carry some of the same mutations? what types of information can scientists learn by studying the genomes of these two populations of rats?