Is W a subspace of the vector space? If not, state why. (Select all that apply.) W is the set of all nonnegative functions in C(−[infinity], [infinity]). W is a subspace of C(−[infinity], [infinity]). W is not a subspace of C(−[infinity], [infinity]) because it is not closed under addition. W is not a subspace of C(−[infinity], [infinity]) because it is not closed under scalar multiplication.