[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]
Since it's a Trapezoid with its non - parallel sides equal to one another,
[tex]\qquad \sf \dashrightarrow \:\angle A + \angle P = 180[/tex]
[ By forming co - interior angle pair ]
[tex]\qquad \sf \dashrightarrow \:\angle A +100 = 180[/tex]
[tex]\qquad \sf \dashrightarrow \:\angle A = 180 - 100[/tex]
[tex]\qquad \sf \dashrightarrow \:\angle A = 80 [/tex]
Now, similarly,
[tex]\qquad \sf \dashrightarrow \:\angle A + \angle R = 180[/tex]
[tex]\qquad \sf \dashrightarrow \: \angle R + 80 = 180[/tex]
[tex]\qquad \sf \dashrightarrow \: \angle R = 100[/tex]
Similarly,
[tex]\qquad \sf \dashrightarrow \angle K + \angle R = 180[/tex]
[tex]\qquad \sf \dashrightarrow \angle K + 100 = 180[/tex]
[tex]\qquad \sf \dashrightarrow \angle K = 80[/tex]
