1) Person A runs around a circular track in 40 seconds. He meets person B coming the other way every 15 seconds. How fast does Person B run around the track in seconds?

2) Five kilometers upstream from his starting point,

a rower passed a raft flowing with the current.

He rowed upstream for one more hour and then rowed back

and reached his starting point at the same time as the raft.

Find the speed of the current.

(Edit: I could not reconstruct the escalator problem. - Dan)