[10 pts] The table shows the diameter at breast height (DBH) for eight hardwood, deciduous trees collected in a 5-meter radius area, as well as the aboveground dry biomass (bm) calculated with the equation from Jenkins et al. (2003). 

 Calculate the total tree carbon per area (in ton C/ha). 

Assume that 50% of the aboveground dry biomass is carbon, and the ratio of 30% of root per aboveground dry biomass. 

Equations and conversion factors:

For Hardwood (maple, oak, hickory, beech): 

Area of a circle = π r² 

1 ton = 1,000 kg

1 ha = 10,000 m²