Answer:
2 × 10 g
Explanation:
The lethal dose 50 (LD50) of Coumarin is 293 mg/kg body mass. The amount of Coumarin that a 70 kg student would have to ingest to reach the LD50 is:
70 kg body mass × (293 mg/kg body mass) = 20510 mg
1 gram is equal to 1000 milligrams. The mass (in grams) corresponding to 20510 milligrams is:
20510 mg × (1 g/ 1000 mg) = 20.51 g ≈ 2 × 10 g