What is the begining of a river called

What were some of the most important native items adopted by europeans ? what impact did they have on european life ?

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.

Which behavior is appropriate in the laboratory? eating a snack while conducting an experiment mixing chemicals as instructed by the lab procedure tasting unknown chemicals to identify them tossing around a football with friends