The geologist C. F. Richter defined the magnitude of an earthquake to be 
where I is the intensity of the quake (measured by the amplitude of a seismograph 100 km from the epicenter) and S is the intensity of a ”standard” earthquake (where the amplitude is only 1 micron = 
cm). The 1989 Loma Prieta earthquake that shook San Francisco had a magnitude of 7.9 on the Richter scale. The 1906 San Francisco earthquake was 12times as intense. What was its magnitude on the Richter scale?
a. 12
b. 11
c. 9
d. 14
e. 13
c. 9
Mathematics
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Find Dxy. e13xy + xy = 5[Hint: Use implicit differentiation]
A. - 
B. - 
C. - 
D. - 
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Solve the problem.The floor plan of a building is shown in the figure below. Starting outside, is it possible to walk through each door exactly once, and end up back outside? Justify your answer.
What will be an ideal response?
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Evaluate the cylindrical coordinate integral.
A. 2? B. 28? C. 14? D. 4?
Mathematics
Simplify.
-3
A. 
B. 
C. 
D. 
Mathematics