Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!

Can you name some countries which do not have the alphabet 'A' in them?

When does a USA Potato change its nationality?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

Buy me, smell me or deliver me, I do not change.

Who am I?

You’re out on the water and see a boat filled with people. You look away for a second and look back again, but this time you don’t see a single person on the boat. Why? Hint: The boat did not sink.

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

At a party, there are five people and a whole round cake lying at the centre of the table. Only four people will make a cut and take their piece and the last one will get the remaining piece on the table. How can they make sure that everyone gets a 1/5th of the piece?

All of Jacob's shoes are red except two.
All of Jacob's shoes are green except two.
All of Jacob's shoes are yellow except two.

How many shoes does Jacob have?