Answer:
Option (3)
Step-by-step explanation:
In a right triangle,
Cosine rule →
Sine rule → 
In the given triangle,
By cosine rule,


Or cos(h°) = z ÷ x
Therefore, Option (3) will be the answer.
Answer:
77
Step-by-step explanation:
Add the numbers together, then divide them to how much numbers are there.
74 + 75 + 80 + 76 + 75 + 81 + 78 = 539
Since there are 7 numbers, you divide 539 by 7.
539/7 = 77