Imagine taking a thumbtack between your thumb and forefinger, with
the sharp end on your thumb and the tail end against your forefinger
(even though each end of the tack exerts the same pressure). If you
squeeze, it's immediately painful on your thumb but not your
finger. Why? (Don't refer back to the text.)
Is it possible for two fluids to exert a different pressure on a
submerged object? Explain why or why not?