What angle pair are the marked angles

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

If mary had 320 toy cars and she gave her friend 50 cars and then she gave her brother 72 more cars how much toy cars would mary have left ● explain with proper details

Ineed to know the ordered pairs for this equation i need the answer quick because it’s a timed test