Sequences — practice question

The table presents three sequences. In Sequence A, the 1st term is 28, the 2nd term is 22, the 3rd term is 16, the 4th term is 10, the 5th term is 4, the 6th term is blank, and the $n$th term is blank. In Sequence B, the 1st term is $1/6$, the 2nd term is $2/7$, the 3rd term is $3/8$, the 4th term is $4/9$, the 5th term is $1/2$, the 6th term is blank, and the $n$th term is blank. In Sequence C, the 1st term is $1/4$, the 2nd term is $1/2$, the 3rd term is $1$, the 4th term is $2$, the 5th term is $4$, the 6th term is blank, and the $n$th term is blank.