Learn Hardcore Russian: Отправка письма занимает минуту.

Отправка is a noun meaning “sending” or “dispatch.” It’s the nominalized form of the verb отправить (“to send”), formed with the suffix -ка. In Russian, such nouns denote the action or result of a verb and are always treated grammatically as independent nouns.

Why is письма in the genitive case here?

In the phrase отправка письма, письма (genitive of письмо) indicates what is being sent. Russian often uses the genitive case after abstract nouns like отправка to show possession or the object of the action: “sending of a letter.”

Why do we use занимает instead of a verb like требует or берет?

All three verbs can express time consumption, but with subtle differences:

занимает is neutral and very common: Отправка письма занимает минуту = “Sending a letter takes a minute.”
требует (requires) sounds more formal: Отправка письма требует минуты.
берёт (literally “takes”) is more conversational: Отправка письма берёт минуту. Choosing занимает gives a clear, neutral statement about duration.

Why is минуту in the accusative case without any preposition?