You will be given a definition of a task first, then some input of the task.
In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

Scale insects are oval bugs up to _ millimetres in diameter that tend to resemble a fungus.
Output:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
four