A student tries to measure field of view (FOV) of the eyepiece of his/her telescope, using rotation of the
Earth. To do this job, the observer points the telescope towards Vega (alpha Lyr., RA: 18.5h
, Dec: +39° ),
turns off its "clock drive" and measures trace out time, t=5.3 minutes, that Vega crosses the full diameter
of the FOV. Calculate the the FOV of this telescope in arc-minutes?