What is common among 11, 69, and 88?

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

Can you write down eight eights so that they add up to one thousand?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different. How do you measure 45 minutes?

Can you find the company name in the pictogram below?

You have to fill the below given grid in a manner that every row and column contains the digits 1 to 6. Also, make sure that the squares that are connected with each other must contains the same digit.

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

John was piloting a plane behind a car but was never able to overtake it. Why?