Final answer:
Weighted-average and FIFO equivalent units are the same when there are no beginning work-in-process units, as all costs and work are attributed to units started and completed in that period.
Step-by-step explanation:
The question relates to the determination of equivalent units in cost accounting, specifically within the context of process costing methods.
The weighted-average and first-in, first-out (FIFO) methods would yield the same number of equivalent units in a period when there are no beginning work-in-process units. This situation is described in Option 1. Without any beginning work-in-process units, all work and costs during the period are attributed to the units started and completed during that period only, making the weighted-average and FIFO calculations identical because there's no prior period work or costs to consider.