油脂的酸价升高说明（）。
A.饱和脂肪酸增加
B.不饱和脂肪酸降低
C.不饱和脂肪酸增加
D.游离脂肪酸降低
E.游离脂肪酸增加
参考答案：E
Recently the Ministry of Environmental Protection issued a circular saying that China may adopt flexible working hours and stop school classes_____the highest air pollution warnings.
A．for fear of
B．in terms of
C．on top of
D．in case of
发电机主要有哪些用油、用水、用风系统？它们的作用如何？
