Which vehicle is spelled the same forwards and backwards?

You, me, Will and Mary eat together how do you arrange the chairs? (the way to do this is that it should be a sentence)

We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly. How can that be possible?

A man is trapped in a room. The room has only two possible exits: two doors. Through the first door there is a room constructed from magnifying glass. The blazing hot sun instantly fries anything or anyone that enters. Through the second door there is a fire­breathing dragon. How does the man escape?

What when read from right to left is a servant but when read from left to right is a ruler?