Related Clues:

• Government imposition
• Strive (for)
• See 18-Across
• Put a burden on
• See 65-Down
• Common add-on
• Uncle Sam's take
• The work force
• Bill addition
• One side of a dispute, often
• Partner of parts
• Sales add-on
• Weigh heavily on
• Bill add-on
• Blood, sweat and tears