Оба варианта имеют одно и тоже значение. Только at THE travel agency.

...иначе получается "Как долго она работает в КАКОМ-НИБУДЬ турагенстве".

Правильно))

Что же касается не смысловой, а чисто формальной разницы между Present Perfect и Present Perfect Continuous именно в контексте с How long, то формально можно эти два варианта перевести так:
"Как долго она там УЖЕ проработала?" (она продолжает работать и сейчас) [РР];
"Как долго она там работает?" [PPC]
Вполне очевидно, что и по-русски никакой смысловой разницы нет.

👍🏼

Both questions ask about Jane’s duration at the travel agency, but there’s a slight nuance. "How long has Jane worked…" suggests a focus on the total time, while "How long has Jane been working…" emphasizes the ongoing nature of her work. Language details like this are fascinating, and for more insights into travel and culture, check out https://qataralive.com/

Both questions ask how long Jane has been at the travel agency. “How long has Jane worked” focuses on the total time she’s been employed there, while “How long has Jane been working” highlights that she is still actively working and emphasizes the ongoing nature of her job. Both are correct, but the continuous form suggests a more current, continuous action. https://www.feastandslumber.com/hampton-inn-breakfast-hours/

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