Question
Fri July 22, 2011 By:

In 0.67'' ,what is ['']? Why is it used & what is it called ??

Expert Reply
Fri July 22, 2011
'' is the symbol used to denote a unit of angular measure equal to 1/60 of an arc minute('), or 1/3600 of a degree(o). It is called arc second.
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