In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Telescopes come in _ basic types - refractors and reflectors.

Answer: two


Question: Cockatiels average _ to five eggs per nest, with an egg typically laid every other day.

Answer: four


Question: Oceanographers now understand the oceanic circulation much better than _ years ago.

Answer:
ten