Fold a stack of paper that is 0.2 cm thick once, and the thickness of this stack of paper is now ( ) cm.
Pick one
Solution
Answer: A stack of paper is 0.2 cm thick. After folding it once, it becomes two layers of 0.2 cm, which means 0.2 plus 0.2, so it should equal 0.4 cm.
Analysis: This question is related to the addition and subtraction of decimals.
Therefore, the correct answer is .
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