The base of a triangle is 7.9dm, the height is 8dm, what is its area dm**2.
一个三角形的底是7.9dm，高是8dm，它的面积是多少dm**2．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 7.9 * 8</gadget>
<output>31.6</output>

<result>31.6</result>