函数关系：m=20+（n-1） (1<=n<=25)（1）m=20+2*(n-1) (1<=n<=25) (2) m=20+3*(n-1) (1<=n<=25) m=20+4*(n-1) (1<=n<=25) (3) m=a+b*(n-1) (1<=n<=p)
