In a semicircle with a diameter of 10 cm, draw a triangle with the largest area. What is the area of this triangle in square centimeters?
在一个直径是10厘米的半圆内，画一个面积最大的三角形，这个三角形的面积是多少平方厘米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">10 * (5/2)</gadget>
<output>25</output>

<result>25</result>