The answer is 55º since the horizontal lines are parallel. My explanation is correct, but you can measure the angles with a tool called a protractor if you wish to prove my answer.
Note: when measuring the angles, none of them will be 55º but 65º. That doesn't matter though since the exercise requires you to use logic, and not measure anything.
Answer:
[tex] \boxed{\bf~55~degrees~is~the~answer.} [/tex]
Hope it helped,
Happy homework/ study/ exam!
