Final answer:
The more formal sentence is 'Because of the approaching storm, the department meeting has been canceled.'
Step-by-step explanation:
The sentence 'Because of the approaching storm, the department meeting has been canceled.' is more formal than 'The dept. meeting has been canceled because of the approaching storm.'
In the first sentence, the subject is expressed in a complete and grammatically correct form, while the second sentence uses an abbreviation for the word department. In formal writing, it is generally preferred to use full words instead of abbreviations.
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