Abhay

But at the end, there is a try again button, but only relieves some stress... 

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2. General Khan Academy Questions
3. Restarting Course Challenge/Unit Test

This means the mind actually will get very messed up, unless your calm. And if you at least want a very good score, or just want some well-earned practice, It's... annoying. This will not encourage...

1. Community
2. General Khan Academy Questions
3. Restarting Course Challenge/Unit Test

But this takes a lot of time... So I would just continue the test, as that would give some practice.  Yet, this causes demotivation, which will make you unfocused.  The only option is to really do ...

1. Community
2. General Khan Academy Questions
3. Restarting Course Challenge/Unit Test

What I did was put the skip button, and then restart. I then retook the test.  

1. Community
2. General Khan Academy Questions
3. Restarting Course Challenge/Unit Test