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 and remove the mercury from its waste liquids. Three firms have provided quotations on the necessary equipment. An analysis of the quotations provided the following table of costs.

Bidder: Foxhill Instrument

Installed Cost: 70,000

Annual Operating Cost: 5,000

Annual Income from Mercury Recovery: 6500

Salvage Value: 10,000

Bidder: Quicksliver

Installed Cost: 50,000

Annual Operating Cost: 5,000

Annual Income from Mercury Recovery: 2500

Salvage Value: 0

Bidder: Almaden

Installed Cost: 90,000

Annual Operating Cost: 5000

Annual Income from Mercury Recovery: 7800

Salvage Value: 10000

If the installation can be expected to last 15 years and money is worth 12%, which equipment should be purchased?