Question

图 $1$ 称为“堆叠图”。数字表示每个位置上堆了多少个立方体。图 $2$ 显示这些立方体，图 $3$ 显示从正面看到的堆叠立方体视图。

下列哪一个是图 $4$ 中堆叠图的正面视图？

Figure $1$ is called a "stack map." The numbers tell how many cubes are stacked in each position. Fig. $2$ shows these cubes, and Fig. $3$ shows the view of the stacked cubes as seen from the front.

Which of the following is the front view for the stack map in Fig. $4?$

答案：B

知识点：立体几何

难度评级：1410

解答：

注意某一列在正面视图中的高度，是前后两个位置高度的最大值。

左列中，后面的立方体堆较高，高度为 $2$ 。

中列中，前面的立方体堆较高，高度为 $3$ 。

右列的高度为 $4$ 。

所以正确答案是 B。

Note that the height of the column is the maximum height of the front and back columns.

In the left column, we have that the back column is taller with height $2.$

In the middle column, we have that the front column is taller with height $3.$

Finally, the right column has height $4.$

Thus, B is the correct answer.

1999 AMC 8 第 20 题

答案：B

难度评级：1410

解答：

其他年份的第 20 题