Which of the following is an example of the nation exerting its territoriality

Can someone me? i need to have this done as soon as possible! i'm putting 20 points on this!

Suggest 3 different reasons why there is an ageing population in the uk .

To solve this system of equations by elimination, what operation could be used to eliminate the y-variable and find the value of x? 6x + 5y = 2 4x + 2y = 8 a) subtract 2 times the second equation from 3 times the first equation b) subtract 3 times the second equation from 2 times the first equation c) subtract 5 times the second equation from 2 times the first equation d) subtract 2 times the second equation from 5 times the first equation