Answers
One question per page, answered in the first sentence. The ones worth reading are where the honest answer is no.
Several of these contradict what the rest of this market publishes. Catch-all addresses cannot be verified at mailbox level by anyone. Pristine spam traps cannot be detected. A single accuracy percentage describes only the addresses a verifier agreed to judge.
Run a sample through it
100 free checks a month, no card, and the unknowns come back labeled.