4. Suppose we are given a set of cashflows {Ct}t>0. Let do denote the corresponding the Macaulay duration D(i, o). Suppose in addition that there is no cashflows during the time (0,3]. That is Ct = 0 for te [0,3]. At time t = 1, Susan computes the Macaulay duration of the same cashflows. That is, she considers t = 1 as the present time, and a cashflow Ct at time t now becomes a cashflow Ct-1 at time t - 1 for her). Let di denote Susan's answer. Show that di = do - 1. 4. Suppose we are given a set of cashflows {Ct}t>0. Let do denote the corresponding the Macaulay duration D(i, o). Suppose in addition that there is no cashflows during the time (0,3]. That is Ct = 0 for te [0,3]. At time t = 1, Susan computes the Macaulay duration of the same cashflows. That is, she considers t = 1 as the present time, and a cashflow Ct at time t now becomes a cashflow Ct-1 at time t - 1 for her). Let di denote Susan's answer. Show that di = do - 1