【正文】 240 118 179 168 70 94 88 f 1 sv 2 50mm 28mm 3 32mm 2 36mm A 24 5 1 2 3 1 2 3 1 2 3 4 5 25 1 2 1 2 3 4 b f 26 b f T I L 1 l 3 l 3 l 6 l 0 0 0 0 2 b s ― b s / 2 s n n n h 3 b 12h b b 5h f f f 1 b 2 3 3 T I L h h h f b 3 h 3 2 b T h h h I L b h 4 b 1 2 3 4 B 27 ab 25% 20% 1 2 C 3 4 28 1 2 3 C 1 2 3 29 30 6 D 9 1 2 3 I 1