What is Silica?

　　In the year 1824, a Swedish scientist named Jons Berzelius discovered this compound and told the whole world about its presence and significance. H... 続きをみる

Can people sit in the suitcase?

　　Many friends ask a question when buying a suitcase: Can the suitcase hold people? Many businesses will also explain the weight of the suitcase in t... 続きをみる