请回答: (1)上述四则材料分别是哪个朝代的统治措施? ___________________________________________________________________________________________ (2)材料一中的措施哪一项对我国历史影响最为深远? ___________________________________________________________________________________________ (3)请指出材料二中措施的原因与影响? ___________________________________________________________________________________________ (4)由材料一到材料四说明皇权和相权有什么变化? ___________________________________________________________________________________________ |