1. Let 12.0-eV electrons approach a potential barrier of height 4.2 eV.
(a) For what barrier thickness is there no re?ection?
(b) For what barrier thickness is the re?ection a maximum?
2. A 1.0-eV electron has a 2.0 X 10-4 probability of tunneling through a 2.5-eV potential barrier. What is the probability of a 1.0-eV proton tunneling through the same barrier?