- Ohm's Law (V = IR) relates the voltage (V) across a component or circuit, the current (I) flowing through it, and its resistance (R). - For a complete circuit with a voltage source and an equivalent resistance R_eq, the total voltage V supplied by the source is related to the total current I flowing out of the source by V = I R_eq. - The question provides possible pairs of total voltage (V) and total current (I) for an electric circuit. We can calculate the implied equivalent resistance (R_eq = V/I) for each pair: - A) V = 900 V, I = 18 A => R_eq = 900/18 = 50 Ω 54.55 Ω - C) V = 600 V, I = 1 A => R_eq = 600/1 = 600 Ω - D) V = 300 V, I = 2 A => R_eq = 300/2 = 150 Ω - The circuit diagram would define the value of R_eq based on the configuration and values of its components (resistors, etc.). Without the diagram, we must assume that one of these calculated R_eq values corresponds to the actual circuit's equivalent resistance. Assuming option D is correct, the circuit must have an equivalent resistance of 150 Ω when connected to a 300 V source or when a 2 A current flows through it resulting in a 300 V drop.