Copy of Circle in a Square

In the images below there are circles cut out of a square, and in both cases you are given the side length of the squares.
a)Find the area of the grey region of the 2 squares.[br][br]b)What would the area of the grey region, of each image, if the side length of the square was s? [br][br]c)Is there a relationship between the 2 areas?

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