What work can one never finish?

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 number do you get when you multiply all of the numbers on a telephone's number pad?

If a wheel has 54 spokes, how many spaces are there between the spokes?

Who is that with a neck and no head, two arms and no hands? What is it?

No matter how little or how much you use me, you change me every month. What am I?

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

If 21x = 79x, what is the value of x?

Can you decipher the below rebus?

PBLUESAISNUERSES

Can you find the missing piece of the Porsche?