最佳答案:The eleven highways during free, many car owners benefit
最佳答案:The free-toll policy is a good example of how government tries to improve the wa
最佳答案:解(1)设AB段所在直线的解析式为Q=k1s+b1,则据图象可得,解得.∴AB段所在直线的解析式为.又设BC图象所在直线的解析为Q=k2s+b2,同样可得 解得