题型:问答题 简答题 They have made greater progress than________ .A.they had expectedB.expectedC.to be expectedD.expecting 查看答案
题型:问答题 简答题 直流电源标准电压为-48伏时,电信设备受电端子上电压变化范围应为()伏之间。A.(-41.6~-56.4)B.(-40~-57)C.(-46~-66)D.(-47~-68) 查看答案