How many persons are facing to the center of the tables?

Study the following information carefully and answer the questions given below: Eight persons are sitting in two concentric circular table. A1, B2, B3 and A4 are sitting around the inner circle and B1, A2, A3, and B4 are sitting around the outer circle but not necessarily in the same order. Some of them are facing inside and some are facing outside from the table. They have different heights- 78, 81, 90, 105, 122, 137, 140 and 155 (in cm) but not necessarily in the same order. Distance between each of the person is same. B3 sits opposite to A1. Both B1 and B4 are not an immediate neighbor to each other and facing opposite directions. B2 who is 78cm long faces A4. A4 sits 45⁰ Clockwise direction from B4. The one who is 81cm long sits immediate left to B3. Both B3 and A3 are facing in the same direction (in the circle). A2 sits immediate left of B4. The one who is 2nd tallest among all sits 90⁰ anti-clockwise direction from A3. Difference between the heights of A2 and A3 is 15cm. The one whose height is 90cm sits immediate left to the one who is 137cm long. Both A3 and A4 are facing in opposite direction to each other. The one who is 105cm long sits 2nd to the left of the one who is tallest among all. A1 who is the tallest among all sits 135⁰ (either clockwise or anti-clockwise direction) from B1, who faces to the north. A1 does not face inside. B1 does not faces towards the center.