It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

What's a single-digit number with no value?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

Which wheel of car does not rotate when you turn your car right?

Which is the smallest number that you can write using all the vowels exactly once?

Can you find out the total number of triangles in the given figure?

In which direction should the missing arrow point?

What is black when you buy it, red when you use it, and gray when you throw it away?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?