From the above figure, the unknown angles are as follows:

∠d = 125^o (Corresponding angles)

∠e = 180^o – 125^o

= 55^o (Linear pair)

∠f = ∠e = 55^o (Vertically opposite angles)

∠c = ∠f = 55^o (Corresponding angles)

∠a = ∠e = 55^o (Corresponding angles)

∠b = ∠d = 125^o (Vertically opposite angles)