You can fry up to 3 fish at a time. Both sides of the fish must be fried. It takes 2 minutes to fry one side. How many minutes is the minimum time to fry 3 fish?
一次最多能煎3条鱼，鱼的两面都要煎，煎一面要2分钟，煎3条鱼最少要多少分钟．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>