In a certain code, COLD is coded as GSPH, then how is NOT coded in the same way?

Study the following information to answer the given questions:
In a certain code ‘a friend of mine’ is written as ‘4 9 1 6’  ‘mine lots of metal’ is written as ‘3 1 0 9’ and ‘a piece of metal’ is written as ‘7 1 6 3’.

‘ 8 7 3’ would mean

In a certain code language, "HAMMER" is written as "MAHERM". How is "MATTER" written in that code language?

In a certain code language, "GRAVYS" is written as "DUJVBY" and "BUTLTS" is written as "WXEVWO" . How is "SPREAD" written in that code language? 

In a certain code language, ‘GROUND’ is written as ‘BMJPIY’. What will be the code for ‘FREAK’ in that code language?

In a certain code language, ‘JAN’ is written as ‘25’, ‘WED’ is written as ’32’. What is the code for ‘SEP’ in that code language?

If SHELF is FURYS, then ZEBRA is

In a certain code language, “ARE” is coded as “87”, and “NOT” is coded as “4197”. How will “CAT” be coded in that language?