Question

please let me know the answer

Answer 1

DE।।BC

Bcz
AD/DB = AE/EC

Answer 2

if it is parallel it should obey parallel axis thorem it states as in triangle ABC &in triangle ADE. AD/DB=AE/EC............as in your question 5.7/9.5=3.3/5.5=0.6 hence DE is parallel to AC