TASK DEFINITION: In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
PROBLEM: Acrobats mount a single bicycle until _ people in all are stacked on top of it.

SOLUTION: ten

PROBLEM: Ozone leaves _ by-products except pure oxygen.

SOLUTION: no

PROBLEM: Some dentists prefer using the oral rinse for three to _ days at a time.

SOLUTION:
five