Question 1Atrazine is one of the most widely used agricultural pesticides in the U.S. that may be applied before and after planting to control broadleaf and grassy weeds. It is used primarily on corn, sorghum, sugarcane, Christmas trees, and other crops. If the oral LD50of Atrazine is 2,000 mg/kg, what is the oral lethal dose in ounces of this pesticide for a 190-lb pesticide applicator?[removed]12[removed]8[removed]6[removed]4Question 2Using a pulse CO-oximeter, a paramedic establishes that the blood of an on-duty fire fighter contains carboxyhemoglobin at a concentration of 55,000 ppm by volume. What would be the symptoms?[removed]No symptoms[removed]Fainting, increased respiration and pulse, coma with intermittent convulsions[removed]Possible death[removed]Respiratory failure and deathQuestion 3Below is a list of chemicals with their oral LD50 in mg/kg (rats). Select the substance that is MOST toxic to rats.[removed]DDT, 87 mg/kg[removed]malathion, 885 mg/kg[removed]carbaryl (sevin), 307 mg/kg[removed]parathion, 3 mg/kgQuestion 4Which health effect is manifested when an injury or disease occurs only after an extensive period of time?[removed]acute[removed]chronic[removed]latent[removed]no effectThe OSHA regulation at 29 C.F.R. §1910.1000(d) requires employers to determine the cumulative exposure of workers to certain gases over an 8-hr work shift using the following formula:E = CaTa+ CbTb+ …. + CnTn 8Eis the equivalent exposure for the work shift, Cis the concentration during any period of time in which the concentration remains constant, and Tis the duration of time in hours of the exposure. The regulation further stipulates that no employee can be further exposed to the gas when the value ofEexceeds the 8-hr time-weighted average limit set for the given substance. If a worker is exposed to ammonia concentrations throughout the workday as follows, 125 ppm for 4 hr; 75 ppm for 2 hr; and 25 ppm for 2 hr, determine the equivalent exposure (E):[removed]28.[removed]75.[removed]88.[removed]90.