Understanding your blood oxygen levels when you are at rest is something that you need to do if you want to make the most of the oxygen that's entering your body. Normal blood oxygen levels for the average American is about 90 to 100 percent oxygen saturation.
The President is responsible for implementing and enforcing the laws written by Congress and, to that end, appoints the heads of the federal agencies, including the Cabinet. The Vice President is also part of the Executive Branch, ready to assume the Presidency should the need arise. The Cabinet and independent federal agencies are responsible for the day-to-day enforcement and administration of federal laws.
The primary duty of the president of the United States is to make sure that all U.S. laws are carried out and that the federal government is run effectively. Although the president may not introduce new legislation - that's the duty of Congress - he does wield veto power over all bills that are approved by the legislature.