REQUIRES FOUR minutes to cross the one-degree longitude.Therefore, the rotation COVERS 15 degrees in one hour.Hence both statements A and B are correct.There is a PRIME meridian at 0o latitude which passes through England.Latitudes are useful to decide the time at any place.Moving east (away from prime meridian) will increase the time by an hour for every 15 degrees.The standard time for India is +5:30, i.e, Indian time is 5.5 hours ahead of the time at 82.5 longitude.