He was in the mountain for a year. He felt as if he was ______

from the outside world.

A．cut out

B．cut off

C．cut up

D．cut through

模拟声音数字化存放是通过采样和量化实现的，若采样频率为44。1KHz，每样本 16位，存放1分钟双声道的声音约占______M字节存储空间。