6个号码复式三中二有多少组

简介：A few days later, Emperor Longwu visited the Zunhua Iron Works in person and inscribed the official commissioning of the iron plant's blast furnace. In this era, iron tools were still not used on a large scale. An important reason was the high cost and backward smelting technology, which led to ordinary people using them. Sorry, if the Ming Dynasty wanted to move from farming to industry, the rise of the steel industry was one of the necessary conditions.