If your hair is brown, purple probably isn't going to show up very well. It's best to bleach your hair before dying it an unnatural color. Like I told you before, the box says 30-40 minutes, but the most I'd leave it on for is an hour. And that's at your own judgment, too.
But China's population statistics can be particularly misleading. Virtually overnight, Chongqing has become the largest city not only in China, but in the world, Time Magazine proclaimed in 2005. But it wasn't true-Chongqing is not the largest city in the world, or even in China.
Tokyo is the capital of Japan. Kawasaki, Sagamihara, and Yokohama these metropolitan areas are included in administrative boundaries of Tokyo, making it most populous area of the world. So Tokyo is standing at number 1 in most populated areas of the world, containing 37,200,000 people in his lap. There is slightly decline seen in the population rate of the Tokyo according to UN, but it will still remain most populated city of the world till 2030 with its 37 million dwellers.