A capacitor of capacitance \(C\) is charged to a potential difference \(V_0\) and then disconnected from the charging source. It is then connected in parallel with an uncharged, identical capacitor of capacitance \(C\). Which of the following correctly gives the ratio of the total final stored electrostatic energy to the initial stored energy, \(U_f / U_i\), and the fraction of the initial energy converted to heat during charge redistribution, \(\Delta E_{\text{heat}} / U_i\)?