在做委托还是自行运输的决策时，企业应该用______。财务分析时要注意货币的时间价值

Everyone has his problems to worry about.

Son: I try to be a good son, but no matter how hard I try, my parents never seem to be satisfied. They think I should eat healthier food, I should wear nicer clothes, and I should get better grades. And according to them, my hari should be shorter, my room should be neater(整洁), and my friends should be more polite when they come to visit. You know it isn’t easy to be a teenager.

Parents: We try to be good parents, but no matter how we try, our children never seem to be satisfied. They think we should wear more fashionable clothes, we should buy a faster car, and we should listen to more interesting music. And according to them, we should be more sympathetic(富有同情心的) when they talk about their problems, we should be more friendly when their friends come to visit, and we should be more understanding when they come late from a Saturday night date. You know it isn’t easy being parents.

根据材料内容，判断正（T）误（F）。

1. There are four people in the boy’s family.

2. The boy’s parents want him to have shorter hair and make his room cleaner.

3. According to the boy, it’s hard to have polite friends.

4. The parents try their best to be good.

5. According to the passage, children always want their parents to eat much healthier food.

已知函数f(x)=log_ax(a＞0,a≠1)，如果对于任意x∈［3，+∞）都有|f(x)|≥1成立，试求a的取值范围.

健身锻炼卫生的原则包括哪些？

EDFA主要分二种泵浦源，以下那一组是EDFA泵浦源工作波长（）

A.1550nm/1310nm

B.1480nm/980nm

C.1550nm/11480nm

D.1310nm/980nm

单位性状