By using (26) , a 600M -byte music CD can be compressed to 50M bytes or less. It can be streamed (downloaded in chunks) so that you can begin listening to the opening bars while the (27) of the file arrives in the background. And, most important, the music files of this kind retain good listening (28) that earlier (29) schemes lacked. That (30) of features makes accessing and distributing music on the web practical for the first time.

A．compression

B．coding

C．transmission

D．playing

下列有关胃食管反流病胃灼热的描述错误的是（）

A.胃灼热是指胸骨后烧灼感

B.常在餐后半小时出现

C.腹压增高时可加重

D.弯腰时可加重

E.卧位可加重