"Area and Arch Length of Circular Sector
'<hr /><div style="max-width:110mm;"><img style="height:60pt;" class="side" alt="sector-angle.png" src="https://calcpad.eu/media/math/area/sector-angle.png"></div>
'Radius -'r = ?
'Angle -'α = ?'&deg;
'<!--
#if α ≤ 180
	'<-->
	'Area
	A = π*r^2*α/360
	'Arch length
	S = π*r*α/180
	'<!--
#else
	'<-->
	'Angle must be less or equal to 180 &deg;
	'<!--
#end if
'<-->1	60