What was the main reason that plantations were so profitable?

a. they planted cotton.
b. they used slaves to do all of the hard labor.
c. plantation owners were clever businessmen.
d. the land was so cheap.

Which statements explain reasons why unconformities occur? check all that apply. rocks along a fault break and move. igneous rock forms at earth’s surface. rocks erode and sediment is deposited. no sediment is deposited over a long time. igneous rock forms between sedimentary layers.