A young investor purchases shares in a firm for $112. The investment banker uses a 50% initial margin and a 35% maintenance margin for accounts of this type. The price of this stock falls to $56. The amount the investor would be required to deposit in the account is closest to:

a. $0.00

b.$14.80

c. $19.60 <-- this is supposed to be the answer but I don't know how to get here.

d. $28.00