1. The threshold/NOEL level found for a particular chemical from animal studies is 0.003 mg/kg body weight per day. The only source for the chemical is freshwater fish, where it occurs at an average level of 0.2 ppm. What is the maximum average daily consumption (g) of such fish that would keep exposure level below the ADI or RfD for the compound?
2. What is the calculated value of the partial pressure(atm) of O2 in acid mine water of pH 1.100, in which [Fe3+] = [Fe2+]?
3. What is the fraction of NTA present after HT2- has been brought to equilibrium with solid PbCO3 at pH 7.00, in a medium in which [HCO3-] = 1.50E-3 M?
4. Calculate the mass percent of methanol, ethanol, and MTBE (answers must be received in that order) that must be present in gasoline to yield a mixture of 4.4 % oxygen by weight.
5.Given that the average TEQ of animal-based foods is about 0.9 pico-grams of TCDD equivalent per gram, and that the LD50 for 2,3,7,8-TCDD is about 0.001 mg/kg body weight, what mass(kg) of animal-based food would you have to consume to ingest a fatal dose of it?
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