Lucio F. answered 04/25/19
PhD in Physical Chemistry + BS in Chemistry w/ minor in Mathematics
Try this site.
quantummechanics.ucsd.edu/ph130a/130_notes/node149.html
Prefllection = [(k-k')/(k+k')]2
for x<0, k =[(8mE(π2/h2)]1/2
and x>0 k' =[(8m(E-Vo)(π2/h2)]1/2
E = 5 eV
Vo = 2 eV
Prefllection = [(k-k')/(k+k')]2 = [(51/2-(5-2)1/2)/(51/2+(5-2)1/2]2 = (51/2-31/2)2/(51/2+31/2)2= (0.254/15.7) = 1.6%
Ptransmission = 100%-1.6% = 98.4%