【简答题】(1)In economics, inflation is a sustained increase in the general price level of goods and services in an economy over a period of time.(2)Inflation occurs whenever the demand for goods and services ...
【单选题】催化剂的哪项属性,对催化裂化反应中氢转移反应影响最大?
【简答题】植物细胞的生长通常分为三个时期: 、 和 。
【单选题】以下哪一种哲学成为了我国封建社会的意识形态()?