There are 6 cylindrical columns in front of the school auditorium. The circumference of the bottom of the columns is 2.5 meters and the height is 5.2 meters. How many liters of paint will be used to paint these columns? (On average, 10 square meters can be painted per liter of paint)
学校礼堂前有6根圆柱形的立柱，立柱的底面周长是2.5米，高5.2米．如果要给这些立柱漆上油漆，一共要用油漆多少升？(平均每升油漆可漆10平方米)
<gadget id="calculator">6 / 10</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2.5 * 5.2 * (3/5)</gadget>
<output>7.8</output>

<result>7.8</result>