If a triangle is drawn inside a semicircle with a diameter of 10 cm, what is the maximum area of the triangle in square centimeters?
直径10厘米的半圆里面画一个三角形，这个三角形面积最大为多少平方厘米．
<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>