TASK DEFINITION: Given a scientific passage and an answer, generate a question for the given answer.
PROBLEM: Passage: When a fluorine atom gains an electron, it becomes a negative fluoride ion. Answer: fluoride ion

SOLUTION: When a fluorine atom gains an electron, it becomes a negative what?

PROBLEM: Passage: and . The electric force is 39 orders of magnitudes bigger. Answer: 39

SOLUTION: How many orders of magnitudes bigger is the electric force?

PROBLEM: Passage: Electromagnetic waves may also be absorbed by matter and converted to other forms of energy. Microwaves are a familiar example. When microwaves strike food in a microwave oven, they are absorbed and converted to thermal energy, which heats the food. Answer: thermal energy

SOLUTION:
Microwaves are converted into what kind of energy in a microwave oven?