Answer:
LD-50: lethal dose 50%, dosage that causes death to 50% of the exposed population
ED-50: effective dose 50%, dosage that causes an effect in 50% of the observed subjects
TD-50: toxic dose 50%, dosage that is toxic to 50% of the observed subjects
These curves do not apply to individuals because it is hard to predict the dosage that will cause a response in an individual, and more practical to predict what percentage of a population will be affected by a certain dosage of a chemical.
Step-by-step explanation: