In order to analyze total costs as a function of machine hours, Rupper Company developed a simple regression model. The model was based on 60 monthly observations of costs and machine hours and had an R-squared of 0.90. The model was: Costs = 14.3A + $161,330 where A is machine hours. If Rupper's machine hours cost for the next month is projected to be 16,000, they should expect total costs to be closest to:

a. $228,800
b. $390,130
c. $161,330
d. $351,117