Identify the hidden meaning behind this picture?

Can you decipher the below rebus?

PBLUESAISNUERSES

What has many teeth, but cannot bite?

While sitting in the Car, John suddenly finds that one of the wheels was missing. John noticed that a killer is approaching towards him. John cannot get out of the car.

How will John escape?

Which is faster, Heat or Cold ? Explain.

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

What has a ring but no finger?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

Six people park their car in an underground parking of a store. The store has six floors in all. Each one of them goes to a different floor. Simon stays in the lift for the longest. Sia gets out before Peter but after Tracy. The first one to get out is Harold. Debra leaves after Tracy who gets out on the third floor.

Can you find out who leaves the lift on which floor?

There are three boxes which are labeled as Rs100, Rs150, and Rs200. One box contains two notes of Rs. 50. The second box contains one note of Rs50 and one note of Rs100 The third box contains two Rs. 100 notes. All boxes are labeled incorrectly.

What is the minimum number of boxes you must check in order to label all boxes correctly?