If R = 3960 statute miles. then one great circle is 2pi(3960) statute miles.

That is for 360 degrees.

In minutes, that is 360*60 minutes

So, 1-minute central angle will subtend

(2pi*3960 statute miles) / (360*60 min)

= 1.15192 statute miles per min.

Therefore, 1 nautical mile = 1.15192 statute miles -------answer.