Final answer:
The United States Congress, under President George Washington, authorized the construction of six frigates in 1794 to strengthen the U.S. Navy and protect American merchant ships from France during the Quasi-War.
Step-by-step explanation:
The construction of six frigates in 1794 was authorized by the United States Congress under President George Washington. These frigates were part of the Naval Act of 1794, which aimed to strengthen the U.S. Navy and protect American merchant ships from attacks by France during the Quasi-War. The frigates included USS United States, USS Constellation, USS Constitution, USS Chesapeake, USS Congress, and USS President.