An underground parking lot has 3 floors, with an average of 140 parking spaces on each floor. How many parking spaces are there in this parking lot?
一个地下停车场有3层，平均每层有140个停车位．这个停车场一共有多少个停车位？
<gadget id="calculator">140 * 3</gadget>
<output>420</output>

<result>420</result>