What primarily set off large-scale migration flows among European countries during the twentieth century? the ability to establish distinctive political structures
the familiar cultural traditions of the host countries
the motivation to reach quotas set by individual countries
the desire to reunite with family members who migrated previously
the removal of migration restrictions

Answer(18);

You're asking in the ap section, so i'll give the ap calculus-style answer. alternatively, you can find the vertex of the parabola and use the "y"-coordinate as the answer.

the maximum height can occur at a critical number, that is, a number  such that  .

the derivative of  can be calculated as follows:



find a value of  that is a zero of the derivative:


this is parabola that is opening downward; we can assume there is a maximum at  .

to find that maximum, calculate  .