$7-1.$ Using the alignment chart from the AISC Specification, determine the effective length factors for columns $IJ,FG,$ and $GH$ of the frame shown in the accompanying figure, assuming that the frame is subject to sidesway and that all of the assumptions on which the alignment charts were developed are met. $($Ans$.1\mathrm{.}27,1\mathrm{.}20,$ and $1\mathrm{.}17)$

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