Question

6. Null, fünf, ..., fünfzehn, zwanzig. 1) acht 2) vier 3) zehn 4) neunzehn

Answer 1

3) zehn

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Answer 2

3) Zehn................

Answer 3

The sequence appears to be counting numbers in German. The sequence is as follows:

Null, fünf, ..., fünfzehn, zwanzig.

In English, this translates to:

Zero, five, ..., fifteen, twenty.

So, the missing number is "3) zehn" which corresponds to "ten" in English.