During which decade did the us pursue a policy of isolation

Under the feudal system, which of the following did lords grant to their vassals?

Which group was responsible for determining the borders of african colonies and later countries

Plz ive been stuck on this question forever. in 1753 george washington was sent on a mission to a. build a fort at the point where the allegheny and monongahela rivers form the ohio river. b. attack the french at fort duquesne. c. attack the french at fort neccessity. d. deliver a message to the french demanding that they leave the ohio river.