A cone and a cylinder with base radii of 2 cm have a volume ratio of 1:3 and the height of the cylinder is 6 cm. What is the height of the cone in cm?
底面半径都是2厘米的一个圆锥和一个圆柱，它们的体积比是1：3，圆柱的高是6厘米，那么圆锥高是多少厘米．
<result>6</result>