Recently, somebody told: "My grandfather was born on the first sunday of the year. His seventh birthday was also on a sunday!" In which year was this grandfather born?

A sultan has 14 daughters. He decides to tell every night four of his daughtes a fairy tale, but in such a way that every night, there will be another combination of four daughters. How many nights will keep the sultan busy telling fairy tales?

At the same time two planes depart from JFK international airport. One plane flies exactly in northern direction, while the other one flies exactly to the east. Both planes fly at the same speed and at the same height. Which plane is after one hour the most far away from JFK?