Bonner company paid $855,000 for a tract of land which included a warehouse and office building. The land, warehouse and office building originally cost $280,000, $180,000, and $340,000 respectively and the current assessed values are $300,000, $200,000, and $400,000 respectively. How should Bonner calculate what value to record for Land?

a. 300,000/ 800,000 x 855,000
b. 280,000/900,000 x 855,000
c. 280,000 /800,000 x 855,000
d. 300,000/900,000 x 855,000