What’s the correct answer ?

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?

Select all of the following expressions that are equal to 2.5.

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?