A student writes the following statements while revising wave optics:
1. "When light passes from a denser to a rarer medium, the refracted wavefront bends towards the normal."
2. "The spacing between successive wavefronts remains unchanged across an interface because frequency is conserved."
3. "For reflection at a plane surface, the reflected wavefront travels equal distances in equal times from the point of incidence as the incident wavefront did before striking."
For each statement:
(i) State whether it is correct or incorrect.
(ii) Give a clear justification based on the behaviour of wavefronts at the interface.