In which of the following cases is it useful to consider the relationship between the length of an oscillating object and its natural period?
Adjusting the speed of a car.
B. Adjusting a clock pendulum.
C. Adjusting tire balance.
D. Adjusting engine mounts.
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A.destructiveB.dissatisfiedC.damagedD.derivative
A. destructive
B. dissatisfied
C. damaged
D. derivative
According to the passage, what has been used to remove deep wrinkles?
Applied drugs.
B. Liquid silicone.
C. Laser treatment.
D. Anti-oxidant.
As implied in the last paragraph, the injectable tan is being researched to meet the demand of the people who ______.
A. refuse to be exposed to the sun
B. refuse to apply suntan creams
C. want to get a tan for beauty
D. want to try gene pigmentation
The italicized expression "gloating upon" probably means ______.
A. thinking with slight guilt
B. seeing with much satisfaction
C. touching with great awe
D. hearing with little delight