Batman attempts to hide out in a Batbox.
The top is a mirrored surface, but the vertical
sides are made of clear Batplastic (refractive
index np = 1.333). It is located x = 2.9 m
horizontally from the edge of the pool.
What is the minimum depth (measured to
the top of the Batbox) that the Batbox can be
below the surface of the water for the Caped
Crusader to remain hidden from the Joker?
Assume: The Joker gets down close to the
water for the best view.
Answer in units of m