Pollution levels in Lake Erie have been modeled by the equation
, where x is the volume of pollutants (in cubic kilometers) and t is the time (in years) (Adapted from R. H. Rainey, Science 155 (1967), 1242-1243). Find the initial pollution level; that is, find x when 
.
?
A. 0.23 km3
B. 0.1 km3
C. 0.40 km3
D. 0.20 km3
E. 0.7 km3
Answer: A
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Given the function f, match the function g with a transformation of f.f(x) = x2 + 8, g(x) = 5x2 + 40
A. f(x + 5) B. 5f(x) C. f(x) + 5 D. f(5x)
Find the vertices of the ellipse.
+ 
= 1
A. (-1, -7), (-1, 17) B. (-1, -15), (-1, 25) C. (-15, 5), (25, 5) D. (-1, -11), (-1, 21)
Determine which of the numbers below is a possible order of magnitude estimate of the quantity described.The total number of breaths taken in his lifetime by a man who lives to be 80.
A. Fifty million B. Ten billion C. Three hundred million D. Three billion
The double line graph below shows the number of Acme Superstores vs. the number of General Superstores. 
In what year was the number of Acme stores approximately equal to the number of General stores?
A. 2000 B. 2002 C. 1999 D. 1998