Piece rate wages require clarifying the bonus per excess unit Steps:

• Basic pay per worker: 40 hours × $50/hour =$2,000; for 20 workers = $40,000.
• Excess units per worker: 145 - 120 = 25; total excess = 20 × 25 = 500 units.
• Piece rate: 20% of $50/hour =$10, but ambiguous if $10 per unit, per hour equivalent, or prorated by time per unit (standard 40/120 = 1/3 hour/unit).
• Total wages = basic + piece bonus, but piece application unclear (e.g., $10/unit yields$5,000 bonus, total $45,000; not in options).

Not enough information.

Final answer: Not enough information.