If the hour hand of a clock is 10 cm long, what is the area swept by the hour hand from 1 o'clock to 7 o'clock in square centimeters?
某钟表的时针长10厘米，那么从1点钟到7点钟时针扫过的面积是多少平方厘米．
<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">30 * 6</gadget>
<output>180</output>

<gadget id="calculator">180 / 360</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3.14 * 100 * (1/2)</gadget>
<output>157</output>

<result>157</result>