Missing information on number of oven setups Steps:

• Calculate total variable direct costs: materials $900 + wages$600 = $1,500 for 1,000 muffins.
• Add production overheads: 20% of direct wages = 0.2 × $600 =$120; total cost so far $1,620 ($1.62 per muffin).
• Oven setup cost is $40 each, but number of setups (e.g., batches) is unspecified, making total setup cost unknown.
• Cannot compute full cost or selling price with 25% profit margin without this detail.

Not enough information.

Final answer: Not enough information.