Answer:
1. Lines c and d
2. Lines a and b
3. Lines a and b
4. Not enough info
Reason: ∠1 ≅ ∠11 but not directly two parallel lines and a transversal
5. Lines c and d
6. Lines a and b
7. Not enough info
Reason: ∠1 and ∠5 are on a single straight line (Not two parallel lines and a transversal)
8. Lines a and b
9. Not enough info
Reason: ∠15 and ∠16 are on a single straight line (Not two parallel lines and a transversal)
10. Lines c and d