At a distance of 15.0 m from a sound source, the intensity level is 60.0 dB. What is the intensity level (in decibels) at a point 2.00 m from the source if the source radiates equally in all directions?
A) 55.7 dB
B) 57.5 dB
C) 75.5 dB
D) 77.5 dB
D
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A 4.00 kg hollow cylinder of radius 5.00 cm starts from rest and rolls without slipping down a 30.0 degree incline. The acceleration of the center of mass of the cylinder is
A. 2.45 
B. 2.98
C. 3.35
D. 3.98
E. 4.05
In 1924, Edwin Hubble proved that the Andromeda Galaxy lay far beyond the bounds of the Milky Way, thereby putting to rest the idea that it might have been a cloud within our own galaxy. What key observation enabled him to prove this?
A) He observed individual Cepheid variable stars in Andromeda. B) He was able to measure the parallax of the Andromeda Galaxy. C) He found that the universe is expanding, and therefore concluded that Andromeda must lie outside our own galaxy. D) He was the first person ever to look through a telescope at the object we now call the Andromeda Galaxy.
If the momentum of a ball is doubled, then the kinetic energy is
A. 0.5 times larger. B. 2 times larger. C. 3 times larger. D. 4 times larger. E. 5 times larger.
The focal length of the lens of a simple camera is 40 mm. In what direction must the lens be moved to change the focus of the camera from a person 25 m away to a person 4.0 m away?
A) does not make any difference B) sideways from the film C) away from the film D) towards the film