Length of DA: 90°
They are placed on a obtuse angle, which is 180° and DA are also placed on a right angle, so that means 180°-90°=90°
Length of AB: 180°
Their placed on a obtuse angle, therefore it will just be 180°
ADF=BDE because, both of them are right angles. This means their degrees will equal (90°=90°).
Hopefully this helps, sorry if I turn out to be wrong!