I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

What does this rebus mean?

O
N
C
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TIME

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

Today, I celebrated my 32nd birthday but I was born in 1972.
How is this possible?

I am the fastest animal but cannot climb the tree. What am I?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

I’m tall when I’m young, and I’m short when I’m old. What am I?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

Find the number of squares in the below picture

In The 1st month of this year(the year 2013), I noticed that the date 13-1-13 (13 January 2013) is special.

This date is special as:

Date * Month = Year.

Can you figure out which year of this century has a maximum number of such dates?