11. Given that $2014 \mathrm{ab}$ is both a multiple of $\mathbf{3}$ and a multiple of $\mathbf{5}$, how many such six-digit numbers are there?
【Analysis】7
$$
\begin{array}{l}
b=0, a=2,5,8 \\
b=5, a=0,3,6,9 ; \\
3+4=7
\end{array}
$$