A cylindrical cistern with a bottom radius of 4 meters and a height of 4 meters is plastered with cement along the sides and bottom of the cistern. If 5 square meters can be painted per kilogram of cement, how many kilograms of cement are needed in total?
一个圆柱形蓄水池，底面半径4米，高4米，沿着这个蓄水池的四周及底部抹水泥．如果每千克水泥可涂5平方米，一共需多少千克水泥？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">3.14 * 8 * 4</gadget>
<output>100.48</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16 * 4</gadget>
<output>200.96</output>

<gadget id="calculator">100.48 + 200.96</gadget>
<output>301.44</output>

<gadget id="calculator">301.44 / 5</gadget>
<output>60.288</output>

<result>60.288</result>