The Affordable Care Act (ACA)enacted major changes to the health care system after its passage in 2010.Describe the three main features of the ACA as it was passed by Congress,and discuss how the Supreme Court has ruled on the constitutionality of various features of the ACA.

There are two components to this question.
a.Main features of the Affordable Care Act: The ACA had three key features: the first was the creation of state-based insurance exchanges where individuals could buy health insurance,along with insurance regulation that would prohibit insurers from denying benefits for a variety of reasons such as preexisting conditions.The second provision,known as "the individual mandate," required uninsured individuals to purchase health insurance; those who do not have insurance are subject to a fine (scheduled to rise over time)of 1 percent of yearly household income or $95,whichever was larger.The third major provision was a set of subsidies to help the uninsured and small businesses purchase insurance as well as an expansion of the public programs Medicaid and the State Children's Health Insurance Program (SCHIP).The Medicaid expansion made more people eligible for the program by opening it to people with incomes up to $27,724 a year.
b.Supreme Court decisions: In 2012,the Supreme Court upheld the constitutionality of the "individual mandate" through Congress's power to tax but also ruled that Congress did not have the power to take existing Medicaid funds away from states if they did not comply with the Medicaid expansion requirements.