A.10°-15°,且不應(yīng)大于30° B.10°-15°,且不應(yīng)大于45° C.15°-25°,且不應(yīng)大于30° D.15°-25°,且不應(yīng)大于45°
A.1m B.2m C.4m D.8m
A.3個月 B.6個月 C.12個月 D.24個月