(A)∀d(R(d)⋀~C(d)) = ∀d(~(~R(d) V C(d))) (taking negation common)
=∀d(~(R(d)->C(d)))= All days are not Rainy days and also are not Cold
(B)∀d(~R(d)->C(d))=The day which are not Rainy day are Cold
(C)∃d(~R(d)->C(d))=∃d(R(d)VC(d))=Some day are Rainy days or some days are Cold
(D)∃d(R(d)⋀~C(d))= Some Rainy days are not Cold
= ~ (∀d(R(d)->C(d))) (taking negation common)
=not all Rainy days are Cold