中国正式加入亚太经合组织是在 [ ] A．1989年 B．1991年 C．199

Software quality assurance is now an emerging sub - discipline of (36) . As Buckly and oston point out, (37) software quality assurance is likely to lead to an ultimate (38) of software costs. However, the major hurdle in the path of software management in this area is the lack of usable software (39) . The development of accepted and generally applicable standards should be one of the principal goals of (40) in software engineering.

A．production

B．planning

C．management

D．research

根据下列条件解三角形，两解的是（   ）

A．b = 10，A = 45°，B = 70°

B．a = 60，c = 48，B = 100°

C．a = 14，b = 16，A = 45°

D．a = 7，b = 5，A = 80°

论述种植绿肥在农业可持续发展中的作用。

芡实治脾虚久泻与其哪些作用有关（）

A.益肾固精

B.益肾健脾

C.收敛止泻

D.除湿止带

E.补养心肝

HM液压油按40℃运动粘度可分为几个牌号？