Riddle Me This

Ok so here's a harder one.

You are on a ship.

Over the side hangs a rope ladder with

rungs

half a meter apart .

The tide rises at half a meter per hour.

At the end of five hours, how much of the ladder will remain above the water assuming that nine rungs were above the water when the tide began to rise?

Something to keep you thinking....

What will you see twice in a week, and once in a year, but never in a day?

House point for the first corect post