用化学知识解释两种物理现象。热胀冷缩:解释 ;闻到花香 。
分子间隔发生变化;分子运动
下面程序的结果是( )。 #include<iostream.h> class test{ private: int num; public: test( ); int getint( ) {return num;} ~test( );}; test::test( ) { num=0;} test::~test( ) { cout<<"Destructor is active"<<endl;} void main( ) { test x[3]; cout<<"Exiting main"<<endl;}
A. Exiting main Destructor is active Destructor is active Destructor is active
B. Exiting main Destructor is active Destructoris active
C. Exiting main Destructoris active
D.Exiting main
如果A对a为显性,B对b为显性,C对c为显性,则基因型A/aB/bC/c的个体自交子代中表现型为A_B_cc的个体比例为()。
A.27/64
B.9/64
C.3/64
D.1/64