There are 5 identical pillars in the hall, the circumference of the bottom of the pillars is 3.14 meters, and the height is 4 meters. Paint these pillars, 0.5 kg of paint per square meter, how many kg of paint will be used in total?
大厅里有5根同样的柱子，柱子底面周长3.14米，高4米．给这些柱子涂上油漆，每平方米用油漆0.5千克，一共要用多少千克油漆？
<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">12.56 * 5</gadget>
<output>62.8</output>

<gadget id="calculator">62.8 * 0.5</gadget>
<output>31.4</output>

<result>31.4</result>