A.20s B.25s C.30s
A.星形網(wǎng)絡(luò)結(jié)構(gòu) B.樹形網(wǎng)絡(luò)結(jié)構(gòu) C.環(huán)形網(wǎng)絡(luò)結(jié)構(gòu)
A.0.5~700m3/min B.1~700m3/min C.10~700m3/min