instruction:
In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
question:
Walruses walk with _ flippers over ice and snow.
answer:
four


question:
Zeolites have basically _ different structural variations.
answer:
three


question:
Colour photos use _ layers of silver salts, sensitive to red, blue or green light.
answer:

three