When most people refer to multimedia, they generally mean the combination of two or more continuous media, usually with some user (115) . In practice, the two media are normally audio and video, this is, (116) plus moving (117) .

It should be’ obvious by now that transmitting multimedia material in uncompressed form is completely out of (118) . The only hope is that massive compression is possible. Fortunately, a large body of research over the past few decades has led to many compression techniques and algorithms that make multimedia transmission (119) .

（115）是（）

A.display

B.games

C.help

D.interaction

E.pictures

F.sound

G.web

10.5/0.4KV变压器分接开关有Ⅰ、Ⅱ、Ⅲ档，正常运行在Ⅱ档，当二次侧电压偏低，应将分接开关调到（）。

A.Ⅰ档

B.Ⅲ档

C.可不调