Answer: 25.7 cm
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Step-by-step explanation:
A full circle of radius r has the circumference of
C = 2*pi*r
A semicircle will have us divide this value in half
2pi*r turns into pi*r
The curved distance along the top is roughly pi*r = pi*5 = 3.14*5 = 15.7 cm.
Add this onto the straight line distance along the bottom to arrive at 15.7+10 = 25.7 cm