Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

All crabs have ____ pair of chelipeds and four pairs of walking legs .
one

Seismologists offer ____ major theories for the occurrence of large, deep earthquakes.
three

Sexual reproduction involves meiosis - ____ consecutive cell divisions.

two