Anyone can me with this pg i don't understand what they wan ?

Now a straight line composes or has 180 degrees always remember that while a common acute angle for the first picture top side left is 45 degrees then followed by a right angle which is always 90 degrees then an obtuse angle on the right which is 135 degrees then a reflex angle is when an angle is more than 180 degrees but less than 360 degrees. I hope that you have learned from my discussion

The first option would be correct if it were one half and not one