资金一旦用于投资就不能用于即期消费，所以，从消费者的角度来看，资金的时间价值体现为放弃即期消费的损失所应得到的必要补偿。( )
参考答案：对
已知函数f（x）=2x+a的图象不过第三象限，则常数a的取值范围是 ______．
I became a student ten years . I have been a student 1996.
I have studied here about 10 years.
A. ago, since, for B. ago ,for ,since C. ago, before, for D ago, in, after
