Suppose that the resistors in the various circuit diagrams represented the resistances of lightbulbs. When a lightbulb "burns out," the circuit is open through that particular component, that is, $R$ is infinite. Would the remaining bulbs continue to burn for the following conditions? If so, would the bulbs burn more brightly (draw more current) or burn more dimly (draw less current), if:
(a) $R_{2}$ burned out in the circuit in Part A?
(b) $R_{1}$ burned out in the circuit in Part B?
(c) $R_{3}$ also burned out in the circuit in Part B?
(d) $R_{3}$ burned out in the circuit in Part $\mathrm{C}$ ?