Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

Can you find the six hidden animals in the picture below?

You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

A boy collects white seashells from the sea and brings them home every night. When he has enough of them, he decides to sell them to a trader.

The trader is ready to buy the shells and he asks the boy about the quantity. At this, the boy starts calculating. He has a giant box that contains 3 mini boxes. Two of them have another mini box inside. If the giant box can hold 50 shells, how many brown shells can he sell to the trader?

You have two rectangular wires.

Both of them have property that when you light the fire from one end , it will take 60 minutes to get completely burn.

However, they do not burn at consistent speed (i.e it might be possible 1st 20% burn in 50 minutes and 80% can burn in 10 minutes).

So how could you measure 45 minutes ?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

Find the next number in the sequence

5 12 24 36 ?

Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?