The body of a beverage bottle is a cylinder with a volume of 2.5 liters. Now there are some beverages in the bottle, the height of the beverage is 15 cm when it is upright, and the empty height is 10 cm when it is upside down, how many liters is there in the bottle?
一个饮料瓶的瓶身是圆柱体，容积为2.5升．现在瓶内还有一些饮料，正放时饮料的高度为15厘米，倒放时，空的高度为10厘米，则瓶内的饮料有多少升．
<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2.5 * (3/5)</gadget>
<output>1.5</output>

<result>1.5</result>