How would today’s technology prevent a “union blockage” from being successful?

Union blockage came into existence in America intending to block trading during the civil war. The goal was to prevent necessary supplies from reaching the confederates since the army felt that if the war lasted for a long time, the best supplied military would win the battle.  

In the recent years, technology has changed international trade massively and has also reduced other trade wars and addressed international tariffs. Union blockage could be prevented by the use of methods that help identify shipping containers easily.

separation of church and state? not sure what you mean.

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225