It is a fragment.
Although it has a subject and predicate, it is a subordinate clause as it starts with 'especially', indicating an adjective or adverb clause.
Answer:
Both sentences are statements
Explanation:
The first sentence states that whales are neither dolphins nor porpoises, this is could be wrong or right but it is making a statement, as well as the second sentence, it says that 7+3 is 8, the sentence is wrong, as we can see from doing the math, but it is still making a claim of something that could be wrong or right, that is what makes it a statement.
The prefix of the word (un)beatable means “not”