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A canning factory is able to produce 4,800 cans of soup in one hour. At this rate, in how many minutes can the canning factory produce 400 cans?
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ACT: Science Question #2

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Passage 1

Various methods are used to estimate the number of microorganisms in a culture. One method utilizes a spectrophotometer to measure the density of organisms in a broth medium. Density indicates the quantity of organisms in a given volume.

In this method, a beam of light is passed through the broth medium. The density of microorganisms in the broth is inversely proportional to the intensity of the light that passes through the broth. A meter is used to indicate the percentage of light transmitted through the medium.

The spectrophotometric data are used to produce a graph, such as the one below, that relates optical density to cell number.



Question: In Figure 2, an optical density of 0.9 coincides with a cell number of approximately:


Choices:
A. 40 10 8
B. 5 10 8
C. 4 10 8
D. 3 10 8

The correct answer is C.

Questions like these just ask you to look up information in a graph.


 Reading across from the y-axis at an optical density value of 0.9, 
 the curve intersects at a cell number of  4  ×  108

 

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