Answer:
Step-by-step explanation:
l║m and line t is the transversal line intersecting these parallel lines.
9). If m∠7 = 100°, 
     m∠3 = m∠7 = 100° [Since, ∠3 and ∠7 are alternate interior angles]
10). m∠7 = 95° 
    m∠6 + m∠7 = 180° [Consecutive interior angles]
    m∠6 = 180° - m∠7
    m∠6 = 180° - 95°
    m∠6 = 85°
11. m∠1 = 120°
    m∠1 = m∠5 = 120° [Alternate exterior angles]
12. m∠4 = 20°
    Since, m∠4 = m∠6 = 20° [Vertically opposite angles]
    And m∠6 + m∠7 = 180° [Consecutive interior angles]
    20° + m∠7 = 180°
    m∠7 = 160°
13. m∠3 = 140° 
    m∠3 + m∠6 = 180° [Linear pair of angles]
    m∠6 = 180° - m∠3
             = 180° - 140°
             = 40°
     m∠6 = m∠8 = 40° [Corresponding angles]
14. m∠4 = 30°
     m∠4 + m∠1 = 180° [Consecutive exterior angles]
     m∠1 = 180° - 30°
     m∠1 = 150°
15. m∠4 = 40°
     m∠4 = m∠2 = 40° [Corresponding angles]
16. m∠7 = 125°
     m∠6 + m∠7 = 180° [Consecutive interior angles]
     m∠6 = 180° - 125°
              = 55°
     m∠6 = m∠4 = 55° [Vertically opposite angles]
17. m∠1 + m∠3 = 230°
     Since, m∠1 = m∠3 [Corresponding angles]
     m∠3 + m∠3 = 230°
     m∠3 = 
              = 115°
     m∠3 + m∠6 = 180° [Linear pair of angles]
     m∠6 = 180° - 115°
     m∠6 = 65°