1:47- use the train tracks.  Start with 62 m on top and 1 s on bottom.  There are 1000 m in a km and 0.621 mi in a km.  Then, convert seconds to minutes and then to hours.

1:49- use train tracks again.  a) start with the speed of light 3.00e8 m/s with 3.00e8 m on top and 1 sec on bottom.  Then, covert meters to km and then to miles like in 47.  Then convert seconds to minutes to hours to days to years.  NOW you should have a number with units miles/year.  Multiply this by 1.4 years to get miles


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