几万伏或几十万伏高压电能输送到负荷区后，必须经过不同的降压变压器将高电压降低为不同等级的电压，以满足各种负荷的需要。
参考答案：对
"You'll have to wait for two hours, ________ is, at about 11; 30, ________ the medical report will
come out, "the doctor said to me.[ ]
A. that; when
B. which; that
C. that; which
D. it; whose
803900000000读作______，改写成用“亿”为单位的近似数约是______亿．
