German phrase
Welchen Umfang soll ~ haben?
Meaning
How long should ___ be?
When to use it
It asks how long it should be. A polite, neutral question about an assignment's length.
Example dialogue
Welchen Umfang soll die Hausarbeit haben?
How long should the paper be?
Ungefähr 3000 Wörter wären angemessen.
About 3,000 words would be appropriate.