Which of the following scientists developed the basic principles of modern day genetics?
hippocrates
charles darwin
anton van leeuwenhoek
gregor mendel

roosevelt believed that in light of the country's recent military successes, it was unnecessary to use force to achieve foreign policy goals, so long as the military could threaten force. this belief, and his strategy of “speaking softly and carrying a big stick,” shaped much of roosevelt's foreign policy.

immigrants from northern and western europe continued coming as they had for three centuries, but in decreasing numbers