True or False questions please answer all questions

1. A joint return cannot be filed if the taxpayer and spouse both die in the same tax year. 2. For income tax purposes, improvements made by a lessee (tenant) are income to the lessor (landlord) upon termination of the lease when the premises are returned to the lessor. 3. Cash charitable contributions of less than $250 can only be deducted if the taxpayer has a cancelled check evidencing the contribution. 4. A taxpayer whose spouse died during any of the four years preceding the year in question and who has not remarried may file his/her federal income tax return as a surviving spouse if the individual maintains a household with a dependent child or stepchild living in it. 5. Parties holding title to property as tenants in common will be taxed on their proportionate share of income produced by the property based on their contribution of ownership of the property