Answer: c. 78,000 equivalent units.
Explanation:
Equivalent units for conversion is calculated as:
= Units completed and transferred out + Equivalent ending work in process
Units completed and transferred out:
= Units started into production - Ending units
= 90,000 - 20,000
= 70,000 units
Equivalent ending work in process = 40% * 20,000 work in process units
= 8,000 units
Equivalent units for conversion = 70,000 + 8,000
= 78,000 units