The express train speed is about 180 km/h, and it only takes 4 hours from Cangnan to Shanghai. How many kilometers is it from Cangnan to Shanghai?
特快列车速度约为180千米/时，从苍南到上海只需4小时，苍南到上海有多少千米？
<gadget id="calculator">180 * 4</gadget>
<output>720</output>

<result>720</result>