3. When a surveyor is measuring a piece of land, they first walk 100 meters from point $A$ at a bearing of $35^{\circ}$ north of east to point $B$, then from point $B$ at a bearing of $55^{\circ}$ north of west for 80 meters to point $C$, and from point $C$ at a bearing of $35^{\circ}$ south of west for 60 meters to point $D$, and finally return to $A$ by the shortest distance. Try to answer the following questions:
（1）Draw the diagram.
（2）What is the shape of this piece of land?
(3) Find the area of this piece of land.
3. Brief solution: ( 1 ) As shown in the figure.
( 2 ) This piece of land is a trapezoid.
$$
\begin{array}{c}
\text { ( } 3 \text { ) } S= \\
\frac{1}{2}(60+100) \times 80 . \\
=6400 \text { (square meters). }
\end{array}
$$