â¢ Wait three to four weeks before lifting heavy objects or doing strenuous exercise. Get clearance from your doctor before very strenuous activity or manual labor. If you underwent angioplasty to stop a heart attack, your doctor may ask you to take a stress (treadmill) test three to six weeks after your procedure.
Aggregate demand, or AD, is defined as the total amount of goods and services consumers are willing to purchase in a given economy and during a given time period. Sometimes aggregate demand changes in a way that alters its relationship with aggregate supply, or AS; this is called a shift.. Since modern economists calculate aggregate demand using a specific formula, shifts result from changes in the value of the formula's input variables.
The Aggregate Supply Curve. The aggregate supply curve shows the relationship between a nation's overall price level, and the quantity of goods and services produces by that nation's suppliers. The curve is upward sloping in the short run and vertical, or close to vertical, in the long run. Net investment, technology changes that yield productivity improvements, and positive institutional changes can increase both short-run and long-run aggregate supply.