题型:填空题 单质和氧化物化学式的书写:物质类别物质名称化学式我的发现(书写规则与读法)单质金属单质钠、钾、铝、铜____________非金属单质碳、硫、磷、硅____________氧气、氮气、氯气____________稀有气体单质氦气、氖气、氩气____________氧化物二氧化碳、二氧化锰、四氧化三铁____________ 查看答案
题型:填空题 (a) In the context of value added tax (VAT) distinguish for a supplier, the relevance of supplying a service that is zero rated and a service that is exempt. (5 marks) 查看答案