plz solve this with full calculation!!

Let A={A,B,C,,X,Y} and the corresponding index value of the set A is {i:1,2,3,4,5,6, ..,25. Please choose t=4 (for sampling) for each set of partitioned message. Under these circumstances, P1 maps first letter of each partitioned message, P2 maps second letter of each partitioned message, P3 maps third letter of each partitioned message, and P4 maps forth letter of each partitioned message. If message (m)=ABCDEFBACABA Find out, corresponding cipher-text. [Ignore blank space]