Answer:
Packaging costs - Variable (Sold) .
Sales commissions - Variable (Sold).
Property taxes on general offices - Fixed.
Shipping expenses - Variable (Sold).
Straight-line depreciation of computer equipment - Fixed. President's salary - Fixed.
Salaries of software developers - Fixed.
Salaries of human resources personnel - Fixed.
Wages of telephone order assistants - Fixed.
Costs of providing online support - Fixed.
Users' guides - Variable (Production).
Step-by-step explanation:
Variable costs are incurred only when there is either production or sale of units.
If there is none, there is no variable cost.
However, fixed costs are costs that must be recognized/incurred by the company, not depending on whether there is production or sales.
These costs do not directly influence production or sale of goods.