I'm sorry that you're having so much trouble with RC's... with a week left to your test it can be mentally challenging to not have every question type down. But just remember, it sounds like you are strong in SC and CR, so that will definitely help your verbal score. So here are some recommendations that have helped me with RC:
Here's a good blog post to show you the difference between everyday reading, and GMAT reading. It really takes a strategy... so practice some of these techniques. They should help:
https://gmatclub.com/blog/2011/04/gmat-r ... es-tricky/Also, remember that the GMAT doesn't expect you to be an expert in what the passage is about. If the passage is about black holes, remember, they know you're not an astrphysicist. So skip over all the details that are confusing. They want you to get caught in those details. Just literally skip right over the words you don't understand, and the sentences that include details about astrophysics. They are unimportant and will hold you up, and make you forget what the passage is all about. Just note where they are, and only come back to them if you get a question directly in regards to that detail.
Good luck!