Final answer:
Using Ohm's law, with e = 180 volts and r = 15 ohms, the current i equals 180 divided by 15, which results in 12 amperes.
Step-by-step explanation:
The equation given is Ohm's law, expressed as i = e/r, where i is the current in amperes, e is the electromotive force (emf) or voltage in volts, and r is the resistance in ohms.
Given the values of e = 180 volts and r = 15 ohms, we plug them into the equation to find i:
i = e/r
i = 180/15
i = 12 amperes.
Therefore, the correct answer is: a. i = 12