A. Because of the stress factors.
B. Because of the leisure activities.
C. Because of the TV watching.
D. Because of the general American culture.
A. One third.
B. Almost two thirds.
C. More than two thirds.
D. Almost half.
A. Americans vow to change it.
B. It is not as bad as it used to be.
C. Americans know how bad it is to their health.
D. Americans do not want to give up more sleep.