In Kung-Fu, it's sashes as oppose to belts.
It can take 6 months to a year, depending how well you learn the patterns for a gold sash.
Traditionally, the Kung-Fu system does not have a ranking system. The current ranking system in most Martial Arts is more or less a commercial invention for the sports variant.
it would take 3 or 4 years to get a black belt
It will depend on a number of factors. The biggest two are going to be how hard you train and how often you attend classes. Most styles have set a minimum of 3 years to obtain the first degree black belt. The average in the style I study seems to be closer to 5.
professionally : how ever it long it takes you to get to 4th dan (takes about three year to go to white to black) each dan could take years to get what karate masters say: 10,000 hours
It depends were you live.
They take exams like any other belt, but for this one they might be asked to do even every kata ever learnt.
It depends on you're natural talents and on the belt you're trying to achieve
5 years minimum. Depends on how much yu put into it. You could be a white belt for 6 years.
You will have to study the techniques and kata for three to five years and pass the required tests. It takes that long to become proficient with the basic skills and to develop the correct mind set.
That depends on many factors. Your dedication and practice will have a major affect. Most schools have minimum time frames for promotion, with most saying will take 3 years from the start to reach black belt. Most of the people I know took between 4 and 5 years.
How long will it take to replace a belt tensioner unit and serpentine belt in a lexus 1996 sc300?
karate
No reason that you can't, as long as you take appropriate precautions to keep the uniform clean.