氧化亚氮的不良反应有（）

A.抑制呼吸

B.抑制白细胞和血小板

C.增大体内气体容积

D.恶心呕吐

E.弥散性缺氧

An analyst does research about margin purchase of stocks. An investor purchased 100 shares of a stock selling at $ 60 per share. The investor borrowed the maximum amount allowed by the initial margin requirement of 60 percent. If the stock price increases to $70 per share, the investor's return before commission and interest on the loan is closest to:

A. 16.7%
B. 27.8%
C. 41.7%