A 12-V automobile battery provides the thousands of volts needed to produce a spark across the gap of a spark plug. Which of the following mechanisms is involved?
a. The secondary loop connected to the spark plug has many more turns than the primary loop attached to the battery.
b. The current in the primary coil is reduced quickly.
c. An iron core increases the magnetic flux through the primary and secondary coils.
d. All three mechanisms are involved.
e. Only mechanisms (a) and (b) are involved.
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