The diagram shows a metal plate $$\(O A B C D E F\)$$ consisting of sectors of two circles, each with centre $$\(O\)$$. The radii of sectors $$\(A O B\)$$ and $$\(E O F\)$$ are $$\(r \mathrm{~cm}\)$$ and the radius of sector $$\(C O D\)$$ is $$\(2 r \mathrm{~cm}\)$$. Angle $$\(A O B=\)$$ angle $$\(E O F=\theta\)$$ radians and angle $$\(C O D=2 \theta\)$$ radians . It is given that the perimeter of the plate is 14 cm and the area of the plate is $$\(10 \mathrm{~cm}^{2}\)$$. Given that $$\(r> \frac{3}{2}\)$$ and $$\(\theta< \frac{3}{4}\)$$, find the values of $$\(r\)$$ and $$\(\theta\)$$. ................................................................................................................................................................ . ................................................................................................................................................................ . ................................................................................................................................................................ . ................................................................................................................................................................ . ................................................................................................................................................................ . 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