To solve this problem you must apply the proccedure shown below:
1. You must apply the Law of Cosines, as you can see in the figure attached. Then:
- The first ship travels at
in for two hours. Therefore, the side
is:

- The second ship travels at
for
. Therefore, the side
is:

- Now, you can calculate
:

The answer is: 
Answer:
Which i think is the first one, there may just be a typing error.
Step-by-step explanation:
A polynomial of order n has the following format:

In which a is the leading coefficient,
are the roots.
If a root appears m times, they are said to have multiplicity m.
Leading coefficient of 1 and roots 21 and 31 with multiplicity 1

So the correct answer is:

Which i think is the first one, there may just be a typing error.
The answer to the question
I’m not sure if I get the question, but the second one would be a fact and the others are all statements. I hope this helps :)
126 because if you multiple 21 and 6 it’s gives you 126