Microwaves of intensity I =100 W/m^2 and wavelengthl =1cm are emitted by an antenna located in S at 500 m above the level of a frozen lake (n = 1.31 ). A P-antenna receives both a wave that propagates horizontally and a wave that is reflected from the icy lake. If the OEM is linearly polarized withg i = 90 degrees, determine the intensity in P and say whether there is constructive or destructive interference.