There are 41 sections of trucks and bodies, each section of which is 30 meters long, and the interval between sections is 1.5 meters. This truck passes through the cave at a speed of 1.5 kilometers per minute. It takes exactly 2 minutes. How long is the cave in meters? ．
一列货车及车身共41节，每节车头及车身长都是30米，节与节间隔1.5米，这列货车以每分钟1.5千米的速度过山洞，恰好用2分钟，这个山洞长多少米．
<gadget id="calculator">1.5 * 2 * 1_000</gadget>
<output>3_000</output>

<gadget id="calculator">41 * 30</gadget>
<output>1_230</output>

<gadget id="calculator">41 - 1</gadget>
<output>40</output>

<gadget id="calculator">40 * 1.5</gadget>
<output>60</output>

<gadget id="calculator">1_230 + 60</gadget>
<output>1_290</output>

<gadget id="calculator">3_000 - 1_290</gadget>
<output>1_710</output>

<result>1_710</result>