（）是指在规定时间内能正常发芽的种子粒数占供试种子粒数的百分率。 A.发芽率 B.发

制作馒头时，馒头发大而松软的原因是  [ ]

A．酵母菌发酵产生了二氧化碳

B．酵母菌发酵产生了酒精

C．馒头中的水分变成了水蒸气

D．乳酸菌发酵产生了二氧化碳

预热带、煅烧带、冷却带比例为15%、50%、35%时煅烧带（）。

A．上

B．下

C．不变

With respect to major bond markets around the world, which of the following statements is most accurate

A. Investors in one country that acquires bonds issued by the government of another country are believed to be risk-free.
B. The factors that affect yield spreads in the U. S. are different than the factors that affect yield spreads in other countries and between countries.
C. An investor in one country that buys bonds denominated in the currency of another country has unknown cash flows in the investor's domestic currency.

一般情况下，冷凝器的出液口应比贮液器的进液口至少高( )。

A．200mm
B．100mm
C．300mm
D．150mm

一颊部穿通伤患者，前来急诊

对此类创伤的处理原则是

A．抗感染

B．止血

C．减少畸形，恢复面形

D．关闭创口，消除创面

E．以上几点都对