Why does Wolfram|Alpha have a hard time with basic unit conversions?

Questions
1

For instance, this works just fine and produces a reasonable answer:

 (2577 miles / (speed of light)) in milliseconds           ==>  13.83 ms

But this fails, with the question being interpreted incorrectly:

 ((distance from SF to NY) / (speed of light)) in milliseconds   ==>  [?] distance from San Francisco to New York -> Quantity[2577, "Miles"]

Is there a different way to ask this question that should work?

2

Well, after further research, I’ve found this this approach (though unintuitive) works:

(distance from SF to NY in meters) / (speed of light in meters per millisecond)  ==> 13.83 ms