Many reasons in a free market capitalistic system; their product or service is not in great demand, their product /service is not the best one on the market in terms or quality/price, their product/service does not have enough publicity to sell well, big corporate companies (amazon, walmart, etc.) have a monopoly on most goods and services and sell them at lower prices while underpaying/ overworking workers
What? I dont understand the question in this ?
Answer:
Once, After
Explanation:
Both words will work here, signifying an action to be done after the letter is received by the speaker.
Hope this helps!