TASK DEFINITION: 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.
PROBLEM: Fish kills can occur when oxygen is less than ____ ppm.

SOLUTION: three

PROBLEM: Sexual reproduction involves the union of cells from ____ parents.

SOLUTION: two

PROBLEM: Many bacteria have plasmids with ____ obvious function.

SOLUTION:
no