______every magnet is surrounded by a magnetic field.
A. It is believed that
B. It believes that
C. It believed that
D. It's believing that
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______I have made no arrangements to deal with such cases.
A. It appear that
B. That appears
C. They appear that
D. It appears that
______ that the first cheese was probably made more than 4000 years ago by nomadic tribes in Asia.
A. The belief
B. Although they believe
C. It is believed
D. Believing
______to space travelers is high acceleration or deceleration forces.
A. That can be dangerous
B. What can be dangerous
C. They can be dangerous
D. It can be dangerous
______unstable and explodes as a supernova is not known.
A. For a star to become
B. How a star becomes
C. Star becomes
D. That a star is becoming