喷雾干燥器按结构可分为哪几大部分？
参考答案：结构分为六个部分：供浆系统、热风系统、雾化器、干燥塔塔体、卸料系统、通风除尘系统。
鸡鸭共一栏，鸡为鸭之半；八鸭展翅飞，六鸡在下蛋，再点鸡与鸭，鸭为鸡倍三，请君算一算，鸡______只，鸭______只．
The investment objective of earning a return on an investment that is at least equal to the inflation rate is called:（）
A. capital preservation.
B. current income.
C. capital appreciation.
