A.5°-15° B.15°-20° C.15°-30° D.30°-45°
A.5×5cm B.8×8cm C.10×10cm D.≥20cm
A.順時(shí)針、逆時(shí)針、順時(shí)針 B.順時(shí)針、順時(shí)針、逆時(shí)針 C.逆時(shí)針、逆時(shí)針、順時(shí)針 D.沒(méi)有順序