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.
Aggregate demand can be illustrated by reference to the circular flow of income. Aggregate demand is generated as income is transferred to spending as a result of the circular flow of income. Income is spent on consumer goods and services (C) plus spending on capital goods by firms (I).