现有企业生产车间噪声容许标准可放宽至()
A.80dB(A)
B.85dB(A)
C.90dB(A)
D.100dB(A)
E.115dB(A)
参考答案:C
有如下程序:#include <iostream>using namespace std;class Base{ private: void fun1() const {cout << "fun1"; } protected: void fun2() eonst {cout << "fun2"; } public: void tim3() const { cout << "fun3"; }}; class Derived: protected Base{ public: void fun4() const {cout << "fun4"; }};int main(){Derived obj;obj.fun1();// ①obj.fun2();// ②obj.fun3();// ③obj.fun4();// ④return 0;}其中有语法错误的语句是( )。
A.①②③④
B.①②③
C.②③④
D.①④
什么叫狗腿度?