I posted this in your other thread:
our 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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