TASK DEFINITION: Given a scientific passage and an answer, generate a question for the given answer.
PROBLEM: Passage: If the experimental value is less than the accepted value, the error is negative. If the experimental value is larger than the accepted value, the error is positive. Often, error is reported as the absolute value of the difference in order to avoid the confusion of a negative error. The percent error is the absolute value of the error divided by the accepted value and multiplied by 100%. Answer: negative

SOLUTION: If the experimental value is less than the accepted value, the error is what?

PROBLEM: Passage: The amount of material left over after a certain number of half-lives can be easily calculated. Answer: pheromone

SOLUTION: What term is used to describe a chemical released by an animal that affects the behavior or physiology of animals of the same species?

PROBLEM: Passage: Joules and calories are the units of energy and heat. Answer: energy and heat

SOLUTION:
Joules and calories are the units of what?