After school, Xiaohong changes the water for the goldfish in the fish tank. She pours 20 liters of clean water into a goldfish tank that is 5 decimeters long, 4 decimeters wide and 4 decimeters high. What is the water depth in the goldfish tank in centimeters?
小红放学后给鱼缸内的金鱼换水，她把20升清水倒入一个长5分米，宽4分米，高4分米的金鱼缸内，金鱼缸内的水深是厘米？
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">20 / 20</gadget>
<output>1</output>

<gadget id="calculator">1 * 10</gadget>
<output>10</output>

<result>10</result>