From your result compute 
and 
, the respective
probabilities for reflection and transmission, for this barrier.
Verify explicitly that 
, and plot
both and as a
function of the incoming wave vector k together on the same plot.
Hint:Note that and have very special values at the
wave vectors 
where 
. This phenomenon is
known as resonant transmission.
Comment on what you think is physically responsible for resonant transmission.