In a certain code GATHERS is written as UBHGRQD.How is SEALING written in that code?

The word GATHERS is divided into three pars : GAT , H , ERS

I : GAT - UBH

The diagonally opposite element is substituted by its immediate following alphabet in the English alphabetical series.

=> G is substituted by H at its diagonally opposite position. Similarly, A is substituted by B at its diagonally opposite position and T by U.

II : H - G

The middle letter is substituted by its immediate preceding alphabet in the English alphabetical series.

III : ERS - RQD

The diagonally opposite element is substituted by its immediate preceding alphabet in the English alphabetical series.

=> E is substituted by D at its diagonally opposite position. Similarly, R is substituted by Q at its diagonally opposite position and S by R.

Thus, code for SEALING :

SEA - BFT

L - K

ING - FMH

$$\therefore$$ SEALING = BFTKFMH