The white and black moths are the same species and thus the same population. Explain how you can have variation of a trait within a population? (think back to mendel genetics and punnett squares)

the answer is c. altitude. hope this ! #brainiac

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.