Question 332765
How long does it take a radar signal to go and return to the originating radar
 unit from an airplane that is 275 mi. away?

A Radar Statute mile is defined as 10.8 micro seconds which is:
"Time for a radar pulse to travel to a target 1 mile away and return"
:
275 * 10.8 = 2970 micro sec or 2.97 millisec