Meals arevery boring. He ________ has the same thing to eat every day.()
A:never
B: usually
C:sometimes
甲、乙、丙、丁四幅图分别是我国东部季风区南、北方四个平原地区的气温年变化曲线图和各月降水柱状图,据图回答:
彩虹的美丽在于它的七色光彩,班级的美丽在于( )
求函数f(x)=( 12 )2x+2×( 12 )x(x≤﹣1)的值域.