The total length of a tunnel is 390 meters. Team A's excavation progress is 14 meters per day, and team B's excavation progress is 12 meters per day. ①How many days will it take to get through this tunnel? ②When the project was completed, how many meters did Team A excavate more than Team B?
一条隧道总长390米，甲队开凿进度14米/天，乙队开凿进度12米/天，同时相向开凿．①需要多少天才能打通这条隧道？②完工时，甲队比乙队多开凿几米？
<gadget id="calculator">14 - 12</gadget>
<output>2</output>

<gadget id="calculator">14 + 12</gadget>
<output>26</output>

<gadget id="calculator">390 / 26</gadget>
<output>15</output>

<gadget id="calculator">2 * 15</gadget>
<output>30</output>

<result>30</result>