American Express Interview Question

1st round: 1. Basic SQL join, 2. Lambda function in python, 3. Difference between a bank and companies like Mastercard, Visa. 4. What happens when you transact using a credit card? 5.Algorithms used in past? 6. CV based questions? 7. How you detect outliers? 8. Puzzle of an insect eating leaf with quantity getting doubled. 9. What factors affect CIBIL score? 10. How you deal with missing data? 11. What will happen if apply regression algorithm to a classification problem? 2nd round: 1.CV based, 2Case Study. 3. 1 puzzle