Three polarizing plates whose planes are parallel are centered on a common axis. The directions of the transmission axes relative to the common...

Three polarizing plates whose planes are parallel are centered on a common axis. The directions of the transmission axes relative to the common vertical direction are shown in the figure below. A linearly polarized beam of light with plane of polarization parallel to the vertical reference direction is incident from the left onto the first disk with intensity Ii = 10.5 units (arbitrary). Calculate the transmitted intensity If when θ1 = 21.0°, θ2 = 35.0°, and θ3 = 59.0°. (Hint: Make repeated use of Malus's law.)