2. There are three or four quadrant angles respectively. The previous set is {a | a = 7/6 pie plus 2k pie, where k belongs to z}
The latter is {A | A = 1 1 Paijia 2k school, where k belongs to Z}
3 (1) 74 of the 45 factions MINUS two factions.
(2) The Erjiu School and the Second School.
(3)-6 faction 143 faction 72.
4. 1 1.25 degrees, 16 minute radians.
5.64 degrees