Draw a rectangle with a length of 4 cm and a width of 2 cm. Draw the largest circle on this rectangle. What is the area of this circle in square centimeters?
画一个长4厘米，宽2厘米的长方形，在这个长方形上画一个最大的圆，这个圆的面积是多少平方厘米？
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<result>3.14</result>