Coding and Decoding Questions

If A = 26 and X-RAY = 40, then WHAT = ?

If "A" denotes "added to", "B" denotes "divided by", "C" denotes "multiplied by" and "D" denotes "subtracted from", then 116 B 29 C 6 A 24 D 45 = ?

If FRIEND is coded as HTKGPF then REVEAL will be coded as:

If SYSTEM is written as RXRSDL.
How can CORRECT be written in that code?

If BUDDHISM is coded as DWFFJKUO then CHRISTIAN will be coded as __________ .

If "+" means "minus", "x" means "divided by", "÷" means "plus" and "-" means "multiplied by", then
300 x 10 – 5 + 36 ÷ 57 = ?

If CROWNED is coded as APMULCB, then how will TAP be coded as?

In a certain code language, "TREASON" is written as "RKWWINX" and "POULTRY" is written as "CNXHYKT". How is "NUMBER" written in that code language?