Nerve signals may travel through nerve or,muscle fibers at speeds as high as two
A. velocities
B. impulses
C. ratios
D. percentage
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In his passage, which of the following is NOT mentioned by the author？
A. How interesting American night life is
B. How busy some Americans are
C. Some Americans' attitude toward sleep
D. People should have more sleep
According to this passage, which of the following would a plant disease result in
A world war.
Border conflicts.
C. Rations of grain and meat.
D. Social upheavals.
When faced with the object or situation they are afraid of, most phobics
A. try to stay away from the object or situation
B. try to pick up courage and fight the object or situation
C. go to their doctors so as to gain freedom
D. know that their fears are the same with other forms of anxiety
A．invitesB．affectsC．needsD．hates
A. invites
B. affects
C. needs
D. hates
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