I was rushing, just need to slow down and do the math out and don't just guess

I've been lacking these past couple days... been very busy lately, but I've been back on track and I'm still improving, just need to slow down and do better at comprehension

Forgot to post 1st mistake noticed neither so narrowed the choices into 2, but the tense was general fact so simple present well i picked present perfect ( have) idk why( idk im finding difficulties understanding what tense need, if someone got any tips or videos pls help) 2st mixed between essential and non essential info i picked (,) when the info was essential and there was ( that) which is considered always essential 3st subject-verb agreement plural/ singular mistake mixed the main subject with a plural noun between 2 commas 4st Can someone explain it, im not sure what is the rule used or why i got it wrong ( photo down) Thanks!

I just really need to learn what I am supposed to do on some of these advanced math problems.

I have been doing 100+ questions for the past 5 days, if it's possible I would like to claim the 5 XP Thanks ! https://www.aniko.ai/sat/student/a54b2d75-d917-41e2-b4dd-46e26c4c4d7d