1. An experiment was conducted to observe the effect of an increase on the potency of an antibiotic. Three 1-ounce portions of the antibiotic were stored for equal lengths of time at each of the following temperatures: 30o, 50 o, 70o, and 90o. The data are shown below.
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Potency Reading, (y)
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38,43,29
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32,26,33
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19,27,23
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14,19,21
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Temperature (x)
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30o
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50o
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70o
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900
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a.) Determine the correlation coefficient, r, between the variables. Is it significant? On what basis?
b.) Determine the coefficient of determination and interpret.
c.) Find the least squares line for the data. Interpret b.
d.) Is b significant? On what basis?
e.) Suppose that a batch of antibiotic were stored at 60o at the same length of time, what is the predicted potency at the end of the storage period?
f.) Construct a 98 % prediction interval when x = 50o.