Meta Data Scientist interview questions

SQL question: given a table of interaction between users (user_a | user_b | day), find number of users who had more than 5 interactions yesterday (assume there is only one unique interaction between a pair of users per day). Product Question: A user satisfaction survey was conducted for two groups of facebook users (each with 50 k sample size). Group1: who had enabled certain login security features Group 2: who had not enabled these security features. It was found that user satisfaction with group1 was 30% lower than with group 2. Why do you think so? Comment on how the survey was conducted?