带式压滤机的工作区间可以分为哪些?
参考答案:重力过滤脱水区、楔形挤压区、预挤压区、挤压去、卸饼区及滤布清洗区。
判断两个量是否成正比例或反比例,说明理由:
房间的面积一定,铺地砖的块数与每块地砖的面积.
--- ____________ does your father go to work?
--- Five times a week.
A.How long
B.How soon
C.How often
D.How many times