A:①②③④⑤
B:⑤④③②①
C:⑤③④①②
D:⑤②③④①
A地的海拔为200米,此时的气温是12℃,B地的海拔是1700米,则B地的气温是( )
When you see an English film or talk with native speakers, observe their facial expressions and g____.
设函数f(x)=|x+1|+|2x﹣1|的最小值为a.
(1)求a的值;
(2)已知m,n>0,m+n=a,求1m+4n的最小值.