ILLUSTRATION 7. $\underset{x\to 2^{+}}{\lim } \left\{\frac{{\left[x\right]}^3}{3}-{\left[\frac{x}{3}\right]}^3\right\}$ is equal to
(a) 0
(b) $\frac{64}{27}$
(c) $\frac{8}{3}$
(d) none of these