How did percy and grover travel back to nyc

name two ways organisms join a population and two ways organisms leave a population. two ways organisms join a population are birth rate and immigration. two ways they leave are death rate and emigration.

explanation:

- "bill clinton ( the 42nd u.s. president, served in office from by low unemployment, declining crime rates and a budget surplus. during clinton's second term, the u.s. economy was healthy, unemployment was low and the nation experienced a major technology boom and the rise of the internet."