—How happy the grandparents are! —Yes, they for fifty years.
A:have been married
B:have married
C:How got married
D:married
下表为某饮水机铭牌的部分参数,其内部简化电路如图所示.当S闭合,S1断开时,饮水机处于保温状态,当S、S1同时闭合时,饮水机处于加热状态.求:C水=4.2×l03J/kg•℃
额定电压
220V
额定功率
加热
1000W
保温
44W
热水器的容量
2L
“低碳生活”是指减少能源消耗、节约资源,从而降低二氧化碳排放的一种时尚生活方式.下列不符合“低碳生活”这一主题的做法是( )
选出与你所听内容相符的图片( )
(Ⅰ)设函数f(x)=|x﹣1a|+|x+a|(a>0).证明:f(x)≥2;
(Ⅱ)若实数x,y,z满足x2+4y2+z2=3,求证:|x+2y+z|≤3.