In the circuit shown in Fig, the 16.0-V battery is removed and reinserted with the opposite polarity, so that its negative terminal is now next to point a. Find
(a) The current in the circuit (magnitude and direction);
(b) The terminal voltage Vac of the 16.0-V battery;
(c) The potential difference Vac= of point a with respect to point c.
(d) Graph the potential rises and drops in this circuit (see Fig).