Approximately what percentage of Rb-87 will remain in the rock when it is 2 billion years
Old?

11. why do citizens have to register to vote?

Chen's research team randomly assigned some newborns and their mothers either to a breastfeeding promotion group (where breastfeeding was encouraged, but not required) or to a normal pediatric care group (where breastfeeding was neither encouraged nor discouraged). which research method did they use?

What are two concepts in the mayflower compact that influenced the founding fathers