Why is the Hole below a Lock?

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?

I am first found in caves, now prolific online; I am a depiction, a drawing, a symbol, or sign. I will convey whichever mood you could wish; or for that matter, a fist, flask, or fish. What am I?

Find the hidden tiger in the given optical illusion ?

Find out which of the given views in the picture is accurately the top view of the given pyramid.

Let's play a word game. Following are some meaningless words that can be completed by adding random letters on either side of the word.

For example, the word "rdo" can be formed into "pardon".

Using the same technique, can you complete the given words?
ecalc
airb
rinci
tibac
uidel
gorit
igna
eyho

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

How many sides does a circle have?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?