Options: the densities of the liquid in the two vessels are equal, the level of the liquid in the two vessels are at the same height, both its limbs are of unequal length, the temperature of the liquids in the two vessels are the same
Options: directly elected by the people on the basis of universal adult franchise, elected by the members of the state legislative assemblies, elected by the members of the state legislative councils, elected by the members of the state legislative councils and state legislative assemblies
Benjamin Franklin was a prolific inventor. He invented the lightning rod, the Franklin stove, studied electricity, discovered the Gulf Stream, started the first library, and on and on. Among his many other inventions, what musical instrument did he invent?