True, false, and, or, not

Which of these sentences are statements (sentences that are either true or false)? Choose all that are.

Which of these statements are true? Choose all that are.

How many of the whole numbers from 1 to 20 make this statement true?

"$n$ is even or $n$ is a multiple of 5."

How many of the whole numbers from 1 to 20 make this statement true?

"$n$ is even and $n$ is a multiple of 3."

Kofi claims: "Every odd number from 11 to 25 is prime." Find all the counterexamples to his claim. Write them separated by commas, like {1, 2}.

(A prime number has exactly two factors: 1 and itself.)

Zara checks the claim "$n \times n + n + 11$ is a prime number" for $n = 0, 1, 2, \dots, 9$ and gets 11, 13, 17, 23, 31, 41, 53, 67, 83, 101 — all prime. What can she conclude?

Which sentence means the opposite of "All the pencils in the box are red"?

The sign on the café door is wrong. It says: "We are open and we have mandazi today." Which sentence must be true?

In Lean, ∀ n : Nat means "for every whole number $n$", → means "then" and ¬ means "not". Which Lean statement says: "Not every number that ends in 2 is divisible by 4"?