Answer:

Step-by-step explanation:
From the Venn diagram, n(AUB)=31
The given probabilities in the option are calculated below:

The only correct option is the probability of B which is 
First distribute 3 to (x-4). that gives you 3x-12. Now your equation is x-2=3x-12. Now you subtract x from 3x. now you're equation is -2=2x-12. then add 12 to the left. You're final answer is 10.
The derivative of
in the direction of a vector
is

With
, we get

and
,

Then
