Which of the following was an effect of the Cold War arms race between the Soviet Union and the United States?
O A. Economic regulation in both nations increased.
B. Governments invested greatly in scientific research.
O C. Both nations expanded their colonial empires.
O D. Fewer civil wars occurred worldwide.

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?