Total operational costs are equal to 600 000 $, which 84% are variable costs. The price per unit is equal to 200 $. The variable costs per unit are equal to 4/5 price per unit. The operating income is equal to:

a. 60 000 $

b. 45 000 $

c. 75 000 $

d. none of the above

e. 30 000 $