Find the measure of dbe if abc is 145 answers 30 60 90 145

Issof claims that the scale factor is 1/2. which statement about his claim is correct

In a small section of a stadium there are 40 spectators watching a game between the cook islands and fiji. they all support at least one of the two teams. 25 spectators support the cook islands and 16 of these support both teams. how many support only fiji?

What is the measure of angle a and angle c ?