In order to calculate marginal cost, producers must compare the difference in the cost of producing one unit to the cost
of
purchasing a unit.
distributing that unit.
producing the next unit.
producing a different unit.

wood carving remains today the primary sculptural art form of the sub saharan continent. african art history shows the earliest wooden sculptures from the 17th c are attributed to the kuba, central zaire but the earliest surviving sub-saharan sculpture is a zoomorphic head found in 1928 in central angola.

i hope this .

when world war i broke out across europe in 1914, president woodrow wilson proclaimed the united states would remain neutral, and many americans supported this policy of nonintervention. however, public opinion about neutrality started to change after the sinking of the british ocean liner lusitania by a german u-boat in 1915; almost 2,000 people perished, including 128 americans. along with news of the zimmerman telegram threatening an alliance between germany and mexico, wilson asked congress for a declaration of war against germany. the u.s. officially entered the conflict on april 6, 1917.