How many electrons does an atom have if the mass number is 31 and the number of neutrons is 16?

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

What approach is required to balance the objectives of sustainable development? balancing the objectives of sustainable development requires a(n) .

Between 2014 and 2016, more than 25,000 children in flint, michigan, drank water that was contaminated with lead from lead pipes. during this time, the city claimed the water was safe to drink. which of these actions could the city have taken to ensure that the drinking water was free from lead?