Three clocks – Ci, C2, and C3 show correct time at 3:00 a.m. Clock C1, uniformly loses 4.5 minutes in an hour, clock C2 uniformly loses 1.5 minutes in an hour and clock C3 uniformly gains 2.5 minutes in an hour. At 11:00 a.m on the same day, by how much time will C1 and C2′ C2 and C3′ C1 and C3 differ respectively?