Final answer:
Firms generally price a product more competitively during the product introduction and growth stages of the product's sales life cycle.
Step-by-step explanation:
In a perfectly competitive market, firms will generally price a product more competitively during the product introduction and growth stages of the product's sales life cycle. During these stages, there is typically less competition and higher demand for the product, allowing firms to set lower prices to attract customers and establish market share.