The conditions that would require beginning a new paragraph are: change in time, change in place, a new speaker, a new topic, and if you want to produce a drama effect. The only condition in the choices above that is not a requirement for you to begin a new paragraph is a new sentence.
A bit more info: Cold War tensions between the U.S. and the Soviet Union from 1967 to 1979. The era was a time of increased trade and cooperation with the Soviet Union and the signing of the Strategic Arms Limitation Talks (SALT) treaties
