Pour 10 liters of water into a cuboid tank with a length of 2.5 decimeters, a width of 2 decimeters, and a height of 6 decimeters. How many decimeters is the height of the water surface from the mouth of the container at this time?
把10升水倒入一个长2.5分米，宽2分米，高6分米的长方体水缸中．这时水面的高度离容器口有多少分米？
<gadget id="calculator">2.5 * 2</gadget>
<output>5</output>

<gadget id="calculator">10 / 5</gadget>
<output>2</output>

<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<result>4</result>