"Area and Arch Length of Circular Segment
'<hr /><div style="max-width:120mm;"><img style="height:70pt;" class="side" alt="segment-angle.png" src="https://calcpad.eu/media/math/area/segment-angle.png"></div>
'Radius -'r = ?
'Angle -'α = ?'&deg;
'<!--
#if α ≤ 180
	'<-->
	'Area
	A = 0.5*(π*α/180 - sin(α))*r^2
	'Arch length
	S = π*r*α/180
	'<!--
#else
	'<-->
	'Angle must be less or equal to 180 &deg;
	'<!--
#end if
'<-->1	60