Meta PM interview questions

1. Replace None value with previous value present in a list. 2. Given a ´dictionary, print the key for nth highest value present in the dict. If there are more than 1 record present for nth highest value then sort the key and print the first one. 3. Given two sentences, you have to print the words those are not present in either of the sentences.(If one word is present twice in 1st sentence but not present in 2nd sentence then you have to print that word too)