The price of the concert is too . I can't afford it.
A:expensive
B:high
C:cheap
D:dear
孔子被尊奉为世界十大文化名人和十大思想家之一,他创立了 ( )
设变量x,y满足约束条件x≥1x-y-4≤0x-3y-4≤0则目标函数z=3x-y的最大值为( )