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Solution: Area of a period: π(4r? -r？ ）=3πr？ ;

Area of comma: π×4r? ÷2=2πr？ ;

Question mark area:

3/4π（4r？ -r？ ）+πr？ = 13 /4 πr？ ;

because

13 /4 πr？ The biggest, so the question mark paint is used in large quantities.

So the answer is: question mark.

This should be understandable.