Question

Where is the red dot located

Answer 1

B.
`√(18)`

Explanation:

While we don't know exactly where it is, we know that it's not A, as
`√(10) < 4`.

We know it's not D, because
`√(12) < 4`

We're left with B and C. We know that
`√(24) > √(20.25) = 4.5` so it's not C either.

B is the only sensible answer.