A cylindrical pool with a bottom diameter of 4 meters and a depth of 2 meters is to be covered with a layer of cement on the sides and bottom of the pool. What is the area of the cement in square meters?
一个圆柱形的水池，底面直径4米，深2米，要在水池的侧面和池底抹上一层水泥，抹水泥的面积多少平方米．
<gadget id="calculator">3.14 * 4 * 2</gadget>
<output>25.12</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">25.12 + 12.56</gadget>
<output>37.68</output>

<result>37.68</result>