What is the symbolism behind where Dr. King gives his speech?

Which of the following makes a true statement about us foreign-policy

As with any small island country, cuba has fewer natural resources than countries such as brazil. this affects their economy in that cuba a) exports only manufactured products. b) exports more products than it imports.. c) must import more products than it exports. d) has imposed trade barriers against the united states.

What greek scientist created a screw to move water for irrigation?