Only when it forms part of the proper noun or when it precedes a person's name or when it is used as a direct address.
Example:
The building permit should be given to Engr. Anna early in the morning.
Have you signed the building permit, Engineer?
No it shouldn't be capitalized.
No, "narwhal whale" does not need to be capitalized in the middle of a sentence unless it is part of a proper noun or title.
it depends on where you place dolphin in a sentence. If it is the first word of a sentence, then yes, it should be capitalized. If it is in the middle of a sentence, then it does not need to be capitalized.
Yes, "Middle Ages" should be capitalized when referring to that specific historical period, as it is a proper noun.
YES! The State Senator is a very importantperson!
No, it shouldn't be capitalized.
I think you need to give an example; the question isn't clear enough.
No, cardiovascular disease does not need to be capitalized unless it is at the beginning of a sentence or part of a title.
No!
No, the word "region" does not need to be capitalized in a sentence unless it is the first word of the sentence or part of a proper noun (e.g. "Pacific Northwest region").
Yes, days of the week are capitalized.
Well, as a common noun it does not need to be capitalized as for it used in this sentence, " I'd like to give you a wedding at my house." but if used as a proper noun it does need to be capitalized. " I loved the Wedding."