Question 210754
E(t) = 69.4 + ,5833t
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where 69.4 = E(0),,,.5833  = (72.9-69.4)/6 
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check,,,,E(6) = 69.4 +6(.58833) = 72.9,,,,,ok
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E(11) = 69.4 + 11(.58833) = 75.8
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