just completed a lab experiment where the purpose was to study a pendulum type impoact testing machine and to perform standard notched bar impact test on 5 Charpy specimens. A Riehle Impact Testing Machine was used to break the specemins and the reading gave 68ft/lb, 66ft/lb, 64ft/lb, 69ft/lb and 63ft/lb. The cross section dimensions of the Charpy were measured to be 0.320in and 0.397in. using this information how can find the impac energy absorbed in breaking the specimens.