Identify fixed and variable costs

Intuit Inc. develops and sells software products for the personal finance market, including popular titles such as Quicken and TurboTax. Classify each of the following costs and expenses for this company as either variable or fixed to the number of units produced and sold:

Property taxes general offices

President's salary

Wages of telephone order assistants

Salaries of human resources personnel

Salaries of software developers

Packaging costs

CDs

Sales commissions

Straight-line depreciation of computer equipment

Users guides

Shipping expenses