The area of the shaded part is equal to the difference between the area of two semicircles with a diameter of 6.8 cm in the figure and the area of triangle ABC. The solution can be obtained by substituting the area formulas of circles and triangles into the data.

1/2×3. 14×(6/2)? + 1/2×3. 14×(8/2)? -6×8÷2

=39.25-24

=15.25cm

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