Replace the question mark with the number below given a simple math problem.

Can you count the number of matches in the picture below ?

I am white when I am dirty, and black when I am clean. What am I?

How far can you walk into the woods?

Can you find the missing piece of the Porsche?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

What month of the year has 28 days?

If 2 workers can complete painting 2 walls in exactly 2 hours.

How many workers would be needed to paint 18 walls in 6 hours?

Which tank will fill first?

In a particular village, only two barbershops exist.

The first shop has a handsome barber with a neat haircut who is handsomely dressed in clean clothes and is extremely humble with his body language. The place is clean and looks hygienic.

In the second shop, you can find a barber with shabby clothing. His hairs are weirdly cut and his clothes still have the stains from last night's dinner. The place is not clean as well and reeks a bit.

You visit the village for the first time and decide to get your haircut. Which barbershop will you like to go for that and why?