The radius of a circle is 4 cm, what is (3/4) the area of the circle in square centimeters?
一个圆的半径是4厘米，这个圆面积的(3/4)是多少平方厘米．
<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">3.14 * 16 * (3/4)</gadget>
<output>37.68</output>

<result>37.68</result>