Logical questions

Tomorrow's yesterday. Yesterday's tomorrow. What is it?

There are two ducks in front of a duck, two ducks behind a duck and a duck in the middle. How many ducks are there?

There are 2 ducks in front of 2 other ducks. There are 2 ducks behind 2 other ducks. There are 2 ducks beside 2 other ducks. How many ducks are there?

The day before two days after the day before tomorrow is Saturday. What day is it today?

I am your mother's brother's only brother in law. Who am I?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

MT_TF_S What are the missing letters?

Mom and dad have four daughters, and each daughter has one brother. How many people are in the family?

2 people in front of 2 people. 2 people behind 2 people, and 2 people beside 2 people. How many people are there?

How many 9's are there between 1 and 100?