利用激光照射治疗肿瘤及脉络膜新生血管时,可以利用激光的()
A.强电场效应
B.弱刺激效应
C.光化学效应
D.压强效应
E.免疫效应
参考答案:C
No wonder his wife complains him. No one can bear him ________ at home, doing nothing day after day.[ ]
A. stay
B. staying
C. to stay
D. stayed
二次函数y=ax2+c(c不为零),当x取x1,x2(x1≠x2)时,函数值相等,则x1与x2的关系是______.