All of the following were essential parts of the southern economy by the mid-19th century except:
a. slavery
b. factories
c. short-staple cotton
d. the plantation system

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 .

a. the astrolabe could determine the correct latitudinal location of the ship