(1) 412°=52°+360°412° = 52° + 360°412°=52°+360° (2) 900°=180°+360°×2900° = 180° + 360° \times 2900°=180°+360°×2 (3) 2130°=330°+360×52130° = 330° + 360 \times 52130°=330°+360×5 (4) −240°=120°+360°×(−1)-240° = 120° + 360° \times (-1)−240°=120°+360°×(−1) (5) −860°=220°+360°×(−3)-860° = 220° + 360° \times (-3)−860°=220°+360°×(−3) (6) −450=270°+360°×(−2)-450 = 270° + 360° \times (-2)−450=270°+360°×(−2)