



 
Hi Muhammad, Let me start with the semicircle. I see the piece of wire in three parts, two parts are of length $r,$ the length of the radius of the circle, and the third curved part of length $C.$ This curved part is half the circumference of the circle and you know the length of the circumference of the circle is $2 \pi r.$ Thus the total length of the wire is $2 r + 2 \pi r.$ But you know the length of the wire is 99 cm so \[2 r + 2 \pi r = 99\] Solve for $r.$ Now you try the quarter circle. Harley  


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