Answer:
6). Option A
7). Option C
8). Y = 62°
Explanation:
6). Let the missing angle = x°
By applying cosine rule to find the missing angle,
cos(x°) =

=

x =

x = 18.92°
x ≈ 19°
Option A is the answer.
7). Let the missing angle = x°
By applying cosine rule in the given triangle,
cos(x°) =

cos(x°) =

x =

x = 13.17
x = 13°
Therefore, Option C is the answer.
8). tanY = 1.8807
Y =

Y = 62°