Your RC should be 100%. To practice, I would just go through the OG and start to read. The Wall Street Journal
and The Economist
should be on your list, as well as books from this thread
. Then, you need to find a method for doing well on RC. Some people read the entire passage, some skim it, some take notes, etc. I read the entire passage and take notes.
Your SC must be close to 100%. Luckily, SC is easy to improve. Take a look at Sentence Correction
by Manhattan GMAT
. Your SC will also improve by reading as suggested for RC.
To improve CR, take a look at PowerScore CR
The GMAT is not scored on percentage correct. You could score a 50% but still get a 730. For example, on one GMATPrep, I only got 40-something percent of the quantitative questions correct, but got a 48. I think you could complete this prep in two weeks, but you will have to work very hard.
For stamina, make sure to schedule your GMAT at a time that works for you. Like to sleep in late? Do not schedule the GMAT for 8:00 AM. Think better in the morning? Schedule it for 8:00 AM. Also, make sure to take some snacks. Have a look at this thread
. I took my GMAT at 1 PM and ate a Snickers bar and a banana during each of my breaks and felt no drain whatsoever during verbal.
I hope that helps
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