To dig a rectangular tank with a length of 6 meters and a width of 3.5 meters, how deep should the tank be dug to make the volume of the tank 42 cubic meters?
要挖一个长方形储水池，长为6米，宽为3.5米，要使这个储水池的容积为42立方米，应挖多深？
<gadget id="calculator">6 * 3.5</gadget>
<output>21</output>

<gadget id="calculator">42 / 21</gadget>
<output>2</output>

<result>2</result>