常见的火源有七种类型,凸透镜与凹面镜属于()。
(A)明火焰
(B)化学反应放热
(C)撞击与摩擦
(D)光线照射与聚焦
参考答案:D
By eleven o'clock tomorrow, we _____ the task. [ ]
A. will have finished
B. will finish
C. have finished
D. finish
下面程序段的输出结果为 public class Test int a,b; Test() a=100;b=200; Test(int x,int y) a=x;b=y; public static void main(String args[]) Test Objl=new Test(12,45);System.out.println("a="+objl.a+" b="+Objl.b);Test Obj2=new Test();System.out.println("a="+Obj2.a+" b="+Obj2.b); A) a=100 b=200 a=12 b=45 B) a=12 b=45 a=100 b=200C) a=12 b=200 a=100 b=45 D) a=100 b=45 a=12 b=200