Because all the contents of BBK are stored and there is no internet connection, the stored mathematics and physics can't be searched for other things.

BBK is a listed company in China, which mainly produces electronic products. Established in 1995 and headquartered in Dongguan, Guangdong. It is committed to the research, development, production, sales and service of audio-visual products. In China, there are more than 65,438+08,000 terminal outlets of shopping malls and supermarkets, and more than 400 4S service experience stores, covering all levels of urban and rural areas in China, and once ranked 425th in the list of top 500 Chinese brands.