加油量的多少，应根据（）、工艺要求、洗净毛本身含油率。
参考答案：原料性质
It is not always easy for the public to see _____ use a new invention can be of to human life. [ ]
A. whose
B. what
C. which
D. that
什么是交流不停电电源系统（UPS）？
