4. In a lossless dielectric ( E = ,u=44) (medium #1), a perpendicular polarized uniform plane wave Z is obliquely incident at an angle e' upon an air half-space (medium #2). Find: (a) angle of incidence for which there is no reflected wave. #1 #2 Air (b) minimum angle of incidence for which there is complete reflection from the air medium (c) angle of transmission for 8 = 20 (d) Describe (using words and simple mathematically expressions) the properties of the wave in the air region for angles of incidence larger than the angle found in (b) and without proof, state the direction of time average power flow in the air region. (e) Sketch the magnitude of the reflection coefficient Iversus incident angle in the range 0 so'