instruction:
In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
question:
Ozone is a gas that consists of _ atoms of oxygen.
answer:
three

question:
Gravity is the weakest of all _ forces but unlike the others it has an unlimited range.
answer:
four

question:
Exhaust gases make _ complete passes through the water.
answer:
two