Liability for tax on death: estate or successor must pay unpaid tax, interest or penalty under the Act. Where a person liable for tax, interest or penalty under the Act dies, successors who continue the business and the deceased's legal representative (out of the estate where the business is discontinued) are liable for such amounts whether determined before or after death; similar joint and several successor liabilities apply on HUF or association partition, firm dissolution, and termination of guardianship or trust, subject to the statutory insolvency exception.