Between x=0 and x=6, the graph of f′(x) lies entirely above the x-axis and encloses an area of approximately 10 square units with the axis. Between x=6 and x=9, the graph lies below the x-axis and encloses an area of approximately 14 square units. Which statement best describes f(9)−f(0)?
a) +24
b) −4
c) +4
d) 0