I need help with this

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

Why can't my rank go i have 1723 points, but my rank is only at ambitious, which is only 250 points! like, (p.s. i know this isn't related to math, but i just don't know why it's doing this and i would really appreciate if someone could tell me whats going on with this)

Three runners competed in a race data were collected at each mile mark for each runner if the runner ran at a constant pace the data would be linear