7. (10 points) There are 6 bricks placed as shown in the figure. A brick can only be removed when there are no bricks on top of it; Mingming wants to remove all the bricks. The number of ways to remove the bricks is $\qquad$.

将上面的文本翻译成英文，请保留源文本的换行和格式，直接输出翻译结果。
First, take away brick No. 1, then you can take away brick No. 2 or brick No. 3,
(1) Take away brick No. 2, then take away brick No. 3,

The order of taking away brick No. 4, brick No. 5, and brick No. 6 is:
$$
\mathrm{P}_{3}^{3}=3 \times 2 \times 1=6 \text { (ways) }
$$
(2) Take away brick No. 2, then take away brick No. 4, there are two orders of taking bricks:
$$
\begin{array}{l} 
2 \text { No. } \rightarrow 4 \text { No. } \rightarrow 3 \text { No. } \rightarrow 5 \text { No., } \\
2 \text { No. } \rightarrow 4 \text { No. } \rightarrow 3 \text { No. } \rightarrow 6 \text { No. } \\
(6+2) \times 2 \\
= 8 \times 2 \\
= 16 \text { (ways) }
\end{array}
$$

Answer: There are 16 ways to take the bricks.
【Solution】Solution: As shown in the figure, the answer is: 16.