A.20 B.50 C.60 D.100
A.及時了解網(wǎng)絡運行情況 B.隨時排除故障 C.定期對傳輸設備、網(wǎng)絡及配套設施進行巡檢、清潔 D.對網(wǎng)絡進行優(yōu)化調(diào)整,解決重大網(wǎng)絡隱患