Definition: In this task, you will use your knowledge about language (and common sense) to determine what element the marked number refers to. The numbers are marked with two underlines around them, like: _ number _. Your answer should be chosen from the given text, and should not contain other words.
Input: Ludwig Von Drake:  For ten years I had followed them , and you know what happens to kids after ten years ? They become teenagers ! One day your kids are asking for hot cereal and the next they 're asking for hotrods . From quart of milk to gallons of gas in _ one _ . The only chance I had to rest and assemble my notes was when they had their car parked .

day