we know that
[length of a circumference]=2*pi*r
diameter=10 cm
r=10/2-----> 5 cm
[length of a circumference]=2*pi*5-----> 10*pi cm
if 360° (full circle) has a length of -----------> 10*pi cm
X°---------------------------> pi cm
X=pi*360/10*pi------> 36°
the answer is 36°