4236d1f5_earn_Math_Robustly_yet_Quickly__2
[0] Guarantee: [1] No question ask. 3 months of 100% full refund guarantee! My payment processor prohibits me to give guarantee longer than 3 months for credit card payment. [3] I am still applying for a refund of 90% of my tuition from my college due to their highly inefficient learning methods. Just kidding ☺. [2] 
Vary. I've never heard a tutor give 100% refund guarantee. I mean how could she afford it?
How to Learn Math Robustly yet Quickly
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