简述外贸部门、外贸企业的经济效益与外贸社会效益的辨证关系。

A. 正确
B. 错误

A web application may override the web container’s implementation classes
B. A web application running in a J2EE product may override classes in the javax.* namespace
C. A web application class loader may NOT override any classes in the java.* and javax.* namespace
D. Resources in the WAR class directory or in any of the JAR files within the library directory may be accessed using the J2SE semantics of getResource
E. Resources in the WAR class directory or in any of the JAR files within the library directory cannot be accessed using the J2SE semantics of getResource

A. 高温、吸热量大
B. 低烃分压大，停留时间短，避免二次反应的发生
C. 反应产物是复杂的混合物
D. 停留时间长

A. 1985年
B. 1986年
C. 1987年
D. 1988年