Calculate the MAD for each of the four techniques in part b$.$ Use only the last $3$ months to compare the same number of months for all methods. Do not round intermediate calculations. Round your answers to the nearest whole number.

MAD $($three$-$month moving average$)$:

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MAD $($weighted three$-$month moving average$)$:

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MAD $($linear trend equation$)$:

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MAD $($exponential smoothing$)$:

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