根据题意得, 66x+2=60x
用多倍体育种获得无子西瓜,下列有关叙述正确的是
You should____ ____ ____ the love of your family.
2015新课标II
如图所示,两平行的带电金属板水平放置。若在两板中间a点从静止释放一带电微粒,微粒恰好保持静止状态。现将两板绕过a点的轴(垂直于纸面)逆时针旋转45°,再由a点从静止释放一同样的微粒,改微粒将()