ABC Inc. is analyzing its maintenance costs over the past year. The following data is available:

• January: Maintenance cost was $2,500 for 500 units produced.
• February: Maintenance cost was $2,800 for 600 units produced.
• March: Maintenance cost was $3,000 for 700 units produced.
• April: Maintenance cost was $3,200 for 800 units produced.
• May: Maintenance cost was $3,500 for 900 units produced.
• June: Maintenance cost was $3,800 for 1,000 units produced.

Using the high-low method, calculate the fixed and variable components of the maintenance costs and formulate the cost function.