3. (20 points) (Present Worth Analysis) A battery manufacturing plant has been ordered to cease discharging acidic waste liquids containing mercury into the city sewer system. As a result, the firm must now adjust the pH level and remove the mercury from its waste liquids. Quotations from three firms are included in the following table of costs. If the installation will last 15 years and money is worth 12%, which equipment should be purchased? Explain why. Bidder Installed Cost Salvage Value Annual Operating Cost Annual Income from Mercury Recovery $6,500 $2,500 $7,800 $10,000 Foxhill Instrument Quicksilver Almaden $70,000 $50,000 $90,000 $5,000 $5,000 $5,000 $0 $10,000