下列不是固体物质的燃烧方式是（）。
A、蒸发燃烧
B、分解燃烧
C、表面燃烧
D、自燃
参考答案：D
Which of the following statements regarding margin accounts is TRUE()
A. A margin call is issued only on short positions.
B. Margin accounts can be used to purchase securities by borrowing part of the purchase price.
C. Margin refers to the amount of funds the investor can borrow.
二尖瓣狭窄并发心律失常最多见的是（）
A.房性早搏
B.阵发性心动过速
C.房颤
D.心动过缓
E.房室传导阻滞
