Question #1 is 55,000 ppm of carboxyhemoglobin by volume equal to 55%?

Question #2 Below is a list of chemicals with their oral LD50 in mg/kg (rats). Select the substance that is MOST toxic to rats.

1. DDT, 87 mg/kg

2. malathion, 885 mg/kg

3. carbaryl, 307 mg/kg

4. parathion, 3 mg/kg (this is my choice)

Question #3 using the cumulative exposure formula of E=C(a)T(a) + C(b)T(b) + C(c)T(c) / 8 what would an employees exposure be is he received 125ppm in 4hours, another 75ppm in 2 hours and 25ppm in 2 more hours.

1. 28

2. 75

3. 88 (This is my choice)

4. 90