[Agda] type of map..<=

[Serge D. Mechveliani]

Who can tell, please, what must be the type of the result of  g  in the 
program

   f : Nat -> Nat
   f n = n + 2     -- may be some complex function

-- g : (xs : List Nat) -> ?
   g xs = map (\lambda x -> (f x) <= 6) xs
?
(here `<=' stands for the math symbol  \<= ).

Thanks,

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Sergei