Depreciation

Please reply soon... (1)my wife have a income from other sources mostly interest income on bank FD if I buy a car in her name can she get depreciation benefits in her return.... (2)if I show sewing and beauty parlour income from this f.y. then will she fall in business category (3) we just have a home loan in joint name then who will get interest benefits both ? Or any one ? If both then in which ratio ?