The end of the feudal systems that defined the European Middle Ages was
primarily caused by "<span>(C) the emergence of trade and a middle class of merchants," since this created more opportunities for people to "break free" from the land-holding system. </span>
the system of electrons surrounding the nucleus of an atom. The name electron cloud is an informal way to describe an atomic orbital.
answer= checks and balances
Explanation:
Federalist No. 51 addresses means by which appropriate checks and balances can be created in government and also advocates a separation of powers within the national government. This idea of checks and balances became a crucial document in the establishment of the modern U.S. system of checks and balances.
A Trireme is powered by about 170 oars men
My guess would be the first one