______(47)A. The delta rhythm will disappear to b

______(47)

A. The delta rhythm will disappear,to be replaced by the activity pattern of brain waves.

B. If you are an average sleeper,your sleep cycle is as follows.

C. In stage 4 sleep people tend to dream.

D. The lower your stage of sleep,the slower your brain waves will be.

E. This period of rapid eye movement lasts for some 8 to 15 minutes and is called REM sleep.

F. This is called stage 1 sleep.