How does our two party system work to protect our liberty?

It doesn't. The system is not something written anywhere into law, but it is a consequence of how the law is structured. At least, it isn't written into legislative law, there it a scientific law describing it.

angle a = 40.6°

step-by-step explanation:

for any right angle triangle we know the pythagoras theorem reveals

hypotenuse² = height²+base²

by this formula we will calculate the length of hypotenuse

h² = 6²+7²

⇒ h =√36+49 = √85 = 9.22

now from the given triangle sin a = height/ hypotenuse

                                                sin a = 6/9.22 = 0.651

therefore

so angle a = 40.6°

answer; i believe that the correct answer is (chronological order);