压缩机中间级排气压力异常上升的可能原因是()。
A.上一级出口冷却器效率低;
B.本级吸、排气阀、活塞环密封不良;
C.吸气不足及管线阻力大;
D.下一级出口冷却器效率低
参考答案:C
______ your brother or you to blame for the broken TV set? [ ]
A. Be
B. Are
C. Is
D. Were
有如下程序: #include<iostream> using namespace std; class Test public:Test() n+=2;~Test() n-=3; static int getNum()return n; private:static int n; ; int Test::n=1; int main() Test* p=new Test;delete p;cout<<"n="<<Test::getNum()<<endl;return0; 执行后的输出结果是( )。
A.n=0
B.n=1
C.n=2
D.n=3