Final answer:
Level, decreasing, and increasing insurance are types of term life insurance. For the related question, Medicare is the public healthcare system that offers insurance primarily to people over sixty-five years old.
Step-by-step explanation:
The basic forms of insurance mentioned in the question refer to term life insurance. Level, decreasing, and increasing insurance are all options that provide coverage for a specified term or period rather than permanent protection. Unlike permanent, whole life, or universal life insurance, term insurance does not accumulate cash value and typically ends after a set period or term.
Answering the student's related question, the public healthcare system in the United States that primarily offers insurance to people over sixty-five years old is Medicare. Medicare is designed to cater to the healthcare needs of older adults and is distinct from Medicaid, which focuses on providing service to individuals and families with limited income and resources.