You are creating a Windows Forms application by using the .Net Framework 3.5.You create an instance of a Backgroundworker component named backgroundWorker1 to process operations that take a long time.You discover that when the application attempts to report the progress，you receive a System.InvalidOperationException exception when executing the backgroundWorker1.ReportProgress method.You need to configure the BackgroundWorker component appropriately to prevent the application from generating exceptions.What should yo do？（） ["Set the Result property of the DoWorkEventArgs instance to True before you attempt to report the progress.","Set the CancellationPending property of backgroundWorker1 to True before you attempt to report the background process","Set the WorkerReportsProgress property of backgroundWorker1 to True before you attempt to report the background process.","Report the progress of the background process in the backgroundWorker1_ProgressChanged event."]
带式输送机的原动力是（）。 ["输送带","托辊","电动机","控制箱"]
“苏联的军事力量，以及它在西方人中间引起的恐惧，长期地模糊了这两个争夺者之间根本的不对称性。”这种“根本的不对称性”主要表现在（）。 ["同盟力量的差距","意识形态的对立","军事力量的失衡","经济水平的差距"]
坚持党的基本路线必须坚持四项基本原则，下列命题中不属于四项基本原则的是（） ["坚持中国共产党的领导","坚持社会主义道路","坚持人民民主专政","坚持改革开放"]
A table was just created on your Oracle database with six extents allocated to it. Which of the following factors most likely caused the table to have so many extents allocated?（） ["The value for MINEXTENTS setting ","The value for PCTINCREASE setting ","The value for MAXEXTENTS setting ","By default, Oracle allocates six extents to all database object"]
汽车公害主要包括（）、（）和（）三个方面。
