Question 14Suppose $a$ and $b$ are single-digit positive integers chosen independently and at random. What is the probability that the point $(a, b)$ lies above the parabola $y = ax^2 - bx?$$\dfrac{11}{81}$$\dfrac{13}{81}$$\dfrac{5}{27}$$\dfrac{17}{81}$$\dfrac{19}{81}$