What does population density measure?
1 . the different species in a community
2 . the area occupied by a population
3 . the number of individuals in a sample
4. the degree of crowding of a population

How did alexander fleming’s research solve a societal problem? he developed ways to treat inherited diseases. he advocated for regular hand washing to kill germs. he discovered a new type of medicine that could treat infections. he discovered the cause of mad cow disease, an emerging disease.