Figure 4—Chads

(a)  Dimpled ChadPunch card with dimpled chad
(b)  Pregnant ChadPunch card with preganant chad
(c)  Hanging ChadsPunch card with multiple hanging chads

Image Credits:    Figures 4a, 4b, and 4c appeared originally in “Chad—From Waste Product to Headline” (http://www.cs.uiowa.edu/~jones/cards/chad.html) and are used with the permission of Douglas W. Jones. 

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