It looks like the OP ran away from his question. Therefore, I will do the first problem just to show those unfamiliar with differential equations (DE) a glimpse of how certain DEs are solved by the separation of variables. As the circuit is shown, the capacitor is energized to 8 volts before the switch is opened. The DE's are determined and solved below. The output voltage is one-third the capacitor voltage.I am trying to solve the questions below could you help me ?