A circular cross-section O ring has the dimensions shown in the figure. In particular,an AS 568A standard No. 240 O ring has an inside diameter D; and a cross-sectiondiameter d of D_{i}=3.734 \pm 0.028 \text { in } d_{i}=0.139 \pm 0.004 \text { in } Estimate the mean outside diameter D and its bilateral tolerance.

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