Your doctor has suggested you have a Nuclear Cardiac Stress Test. A Cardiac Stress Test is a test to show how your heart functions when your heart rate is increased. You will exercise or be given a certain medicine to increase your heart rate. A Nuclear Cardiac Stress test is a specialized test. A very small amount of a radioactive tracer is given in an IV.
Open space is any open piece of land that is undeveloped (has no buildings or other built structures) and is accessible to the public. Open space can include: Green space (land that is partly or completely covered with grass, trees, shrubs, or other vegetation). Green space includes parks, community gardens, and cemeteries. Schoolyards; Playgrounds
Mass is important because of two major factors affecting how things move in space: inertia and gravity. The more mass something has, the more of both it experiences. That is why heavy things (things with a lot of mass) are hard to move. When an object is sitting still, it resists moving, and the more mass it has the more it resists. The amount of thrust needed to move something and how fast it ends up moving are both directly tied to its mass.