The "energy efficiency" of a device is
A) the total energy put into the device divided by its useful energy output.
B) its thermal energy output divided by the total energy put into the device.
C) its total energy output divided by the total energy put into the device.
D) its useful energy output divided by the total energy put into the device.
E) the total energy put into the device divided by its thermal energy output.
D
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Using the following unit conversions: 1.00 fluid ounce = 29.573 ml, 1.00 L = 1000 
density of water = 
the number of fluid ounces in a kg of water is
A. 48.8 fluid ounces. B. 40.1 fluid ounces. C. 33.8 fluid ounces. D. 25.7 fluid ounces.
Typically, no more than a couple dozen potentially hazardous asteroids approach the Earth as close as 0.05 AU each decade
Indicate whether the statement is true or false
A fire hose is turned on the door of a burning building in order to knock the door down. This requires a force of 1000. N
If the hose delivers 40. liters per second, what is the maximum velocity of the stream needed, assuming the water doesn't bounce back? A) 50. m/s B) 25 m/s C) 40. m/s D) 15. m/s E) 30. m/s
Define and explain phase as it relates to wave motion