Which statement best describes the author's purpose in writing this article

In shifting to a defense policy based upon the concept of "flexible response," president kennedy was indicating that he had grave doubts about thevalue of which previous defense policy? a massive retaliationb collective securityc containmentd air power

Was the amassing of men, equipment, and supplies for the 1944 invasion of europe. operation varsity operation nordwind operation dragoon operation overload operation torch

The internal combustion engine was an innovation of