(A)降低 (B)不變 (C)升高 (D)先升高后降低
(A)0.38~0.9m/h (B)0.43~1.27m/h (C)0.5~0.75m/h (D)0.3~1.27m/h
(A)1 (B)2 (C)3 (D)4