【单选题】Which group of people are not mentioned about falling suicide rates?
A.
middle-aged men in the US
C.
old people in the world
【单选题】下列关于键和键槽错误的叙述是 :
A.
钩头楔键的上、下底面是工作面,两侧面是非工作面,所以画楔键连接图时,键的两侧面与轴键槽和轮毂键槽侧面间应留有间隙;
B.
平键的两侧面是工作面,上、下底面是非工作面,所以画平键连接图时,上底面与轮毂键槽顶面之间应留有一定间隙;
C.
一般用移出断面图或局部视图表达平键键槽的结构和尺寸,在这类图中应直接标出键槽的深度 t 或 t1
D.
根据轴径就可在相关国标中查出键和键槽的相关尺寸。
【单选题】What's the main sentence? Life without an externally supported daily plan can lead to higher rates of drug abuse, crime, suicide.
A.
A daily plan can lead to higher rates.
B.
Life can lead to higher rates.
C.
Life supported a daily plan.
D.
A daily plan can lead to drug abuse, crime, suicide.
【单选题】肝 肝脏主要是用来帮助( )消化与吸收。 脏 肝脏主要是用来帮助( )消化与吸收。 主要是用来帮助( )消化与吸收。
【单选题】In developing countries, exchange rates tend to be
A.
floating with some government intervention.
C.
hard to tell from the data.
D.
run by currency boards.