A.吸烟B.慢性支气管炎C.α1-抗胰蛋白酶D.瘢痕附近区
腺泡远端肺气肿见于：
参考答案：D
The one-year spot rate is 6 percent and the one-year forward rates starting in one, two and three years respectively are 6.5 percent, 6.8 percent and 7 percent. What is the four-year spot rate（）
A. 6.51%.
B. 6.58%.
C. 6.57%.
金融机构为了取得资金，将未到期的已贴现商业汇票再以贴现方式向另一金融机构转让的票据行为是指（）。
A.贴现
B.转贴现
C.再贴现
D.回购
