Perhatikan gambar di samping! Tentukan besar sudut yg belum di ketahui?? (Tolong di jawab ya :')

b°=180°-(80°+40°)
=60°
d°=180°-80°
=100°
f°=d°
=100°
g°=180°-f°
=180°-100°
=80°
e°=g°
=80°
h°=180°-(b°+e°)
=180°-(60°+80°)
=180°-140°
=40°
i°=180°-h°
=180°-40°
=140°
j°=h°
=40°
k°=180°-j°
=180°-40°
=140°

b°=60°
d°=100°
f°=100°
g°=80°
h°=40°
I°=140°
j°=40°
k°=140°