The primary difference between a static budget and a flexible budget is that a static budget :

a. Is concerned only with future acquisitions of fixed assets, whereas a flexible budget is concerned with expenses that vary with sales.

b. Includes only fixed costs, whereas a flexible budget includes only variable costs.

c. Is suitable in volatile demand situation while flexible budget is suitable in a stable demand situation.

d. Is a plan for a single level of production, whereas a flexible budget can be converted to any level of production.