About how many years ago was dinosaurs extinct from the earth

how old is the earth

the writings of john locke primarily led the founding fathers to believe that the colonists had a right to overthrow the current british government, since locke held that if a government becomes tyrannical it is the peoples' right to replace it.

'migration rates' are measurements of how many people entering or leaving a country. and if more people are leaving, this could cause a population to change.