题目分析：

~$4024 feet=\frac{4024}{5280} mile$~所求的时间~$t=\frac{4024}{5280}/20=\frac{4024}{5280*20} h$~

所求的时间为minutes=~$\frac{4024}{5280*20} *60=\frac{4024*3}{5280}=\frac{4024}{1760}=2\frac{504}{1760}≈2.2h≈2h$~

综上：答案就是B

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~$4024ft =\frac{4024}{5280} mile$~
~$\frac{4024}{5280} /20=\frac{4024}{(5280)(20)}h$~
~$\frac{4024}{(5280)(20)}×60min≈\frac{4000}{5000}×\frac{60}{20}≈2min$~

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