Learn Danish: Hun tog imod jobbet. - She accepted the job.

While accepterede is perfectly understood and means accepted, the phrasal verb at tage imod (literally to take against or to receive) is often more natural for accepting offers, gifts, or advice. It implies actively welcoming or receiving something that is offered to you.

Why is jobbet spelled with a double 'b' when the root word is just job?

Job is an English loanword that is pronounced with a short vowel sound in Danish. Under Danish spelling rules, when you add a grammatical suffix like the definite neuter ending -et to a short-vowel noun ending in a single consonant, you must double that final consonant. Thus, et job becomes jobbet.

Could you use mod instead of imod in this sentence?

No, you must use imod here. In fixed phrasal verbs like at tage imod (to receive or accept), imod functions as an adverbial particle tied directly to the verb. The related word mod is generally used as a preposition indicating physical direction, like moving towards something.