Answer:
Please look at the attachment for step by step guide and solution.
Answer: 
Step-by-step explanation:
According to the cosine rule

Here, 
Putting values

So, the ship turns by
north of west
Answer:
-7x/6
Step-by-step explanation:
x/2-5x/3
Taking LCM
3x/6-10x/6
(3x-10x)/6
-7x/6
yes it is correct
with parentheses you have to bring EVERYTHING INSIDE THE PARENTHESES to the given power but not if there are no parentheses