Answer:
Sum of interior angles of a triangle = 180°
Sine rule to find side lengths:
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Question 1aa
Given: B = 10°, C = 100°, b = 2
10° + 100° + A = 180°
⇒ A = 70°
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Question 2bb
Given: A = 40°, B = 40°, c = 2
40° + 40° + C = 180°
⇒ C = 100°
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Question 1aa
Given: A = 110°, C = 30°, c = 2
110° + 30° + B = 180°
⇒ B = 40°