单项选择题 What will be written to the standard output when the following program is run？（）   public class Q8499 {   public static void main（String args[]） {  double d = -2.9；   int i = （int） d；  i *= （int） Math.ceil（d）；  i *= （int） Math.abs（d）；   System.out.println（i）；   }   }

填空题 Whatisthenameofthemethodthatthreadscanusetopausetheirexecutionuntilsignalledtocontinuebyanotherthread？（）Fillinthenameofthemethod（donotincludeaparameterlist）.

多项选择题 Whichofthesestatementsconcerningthecollectioninterfacesaretrue？（）