how to write the function for p1_1 :: a -> b -> b p1_1 = undefined p1_2 :: (a -> b -> c) -> (a,b) -> c p1_2 = undefined p1_3 :: (a -> b) -> (b -> c) -> a -> c p1_3 = undefined p1_4 :: (a -> b -> c) -> a -> (d -> b) -> d -> c p1_4 = undefined