can you proce b, d, and e false

a) If Li Is tiomegular w DI D b) If L S L2 and L2 is nonregular, then L is nonregular, c) If L1 is nonregular, then its complement Li is nonregular, d) If L is regular, then L UL2 is regular for any language L2, e) If L and L2 are nonregular, then Lin L2 is nonregular