182. The PCB concentration in Lake Michigan is declining according to a first-order rate law having a rate constant of 0.079 per year. If the PCB concentration in Lake Michigan averaged 0.47 ppt in 1991, what will it be in 2005? In what year will the concentration fall to 0.10 ppt? What is the half-life period of PCBs in this lake? (Answer first with PCB concentration of the year 2005, then the year the concentration will be 0.10 ppt, and lastly the half-life). ***I will be out of town from Friday until Sunday night (with no computer access). If I don't pick up the response during that time, don't think I'm not planning to pay!! I will!!