Dear experts I need help on the attached geometric (Triangle) Figure
The figure, given alongside, shows a triangle ABC whose sides AB and AC are produced upto D a nd E respectively. The bisectors of exterior angles so formed intersect each other at point I. If Ang BAC = 80d and Ang ACB = 50d, find:
1. Ang ECB
2. Ang DBC
3. Ang ICB
4. Ang IBC
5. Ang BIC
Kindly let me know if any theorem is available which explains the geometric properties of this triangle.