Which of the following are the best definitions of the decision variables? – finish time of activity , for – time to be crashed, i.e., saved, for activity ,for – start time of activity , for – time to be crashed, i.e., saved, for activity ,for – finish time of activity , for – start time of activity , for – start time of activity ,for – time finally used by activity i space, for i equals A comma B comma C comma D comma E comma F comma G comma H None of the above.