High concentrations of carbon monoxide co can cause coma and possible death. the time required for a person to reach a cohb level capable of causing a coma can be approximated by the quadratic formula model t=.0002xsq - .316x +127.9, where t is the exposure time in hours necessary to reach this level and 500≤x≤800 is the amount of co present in the air in parts per million (ppm).

what is the exposure time when x = 610?

answer 9.6 hr i got this easy

estimate the concentration of co necessary to produce a coma in 6 hr.
this is the part i can’t find any on.