In a certain code language, 'READS' is written as 'IVZWH', and 'FRIBC…

1   2    3    4   5    6   7     8    9  10  11  12  13

 A   B   C    D   E    F   G    H    I    J    K    L   M

 ↓    ↓    ↓    ↓    ↓     ↓   ↓    ↓     ↓   ↓    ↓    ↓    ↓

 Z   Y    X   W   V    U   T    S    R   Q   P    O   N

26  25  24  23  22  21  20  19  18  17  16  15  14

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THE LOGIC FOLLOWED HERE IS:

AS

R → (OPPOSITE) → I

E → (OPPOSITE) → V

A → (OPPOSITE) → Z

D → (OPPOSITE) → W

S → (OPPOSITE) → H

AND,

F → (OPPOSITE) → U

R → (OPPOSITE) → I

I → (OPPOSITE) → R

B → (OPPOSITE) → Y

C → (OPPOSITE) → X

SIMILARLY

G → (OPPOSITE) → T

H → (OPPOSITE) → S

K → (OPPOSITE) → P

T → (OPPOSITE) → G

X → (OPPOSITE) → C