Draw the largest semicircle in a rectangle. The area of the rectangle is 128 square centimeters. What is the area of the semicircle in square centimeters?
在一个长方形里画一个最大的半圆，长方形的面积是128平方厘米，那么半圆的面积是多少平方厘米？
<gadget id="calculator">8 ** 2</gadget>
<output>64</output>

<gadget id="calculator">64 / 2</gadget>
<output>32</output>

<gadget id="calculator">3.14 * 32</gadget>
<output>100.48</output>

<result>100.48</result>