(a) A light ray could experience total internal reflection while travelling from a rarer medium to a denser medium. True or false? (b) In an optical fiber, the cladding has to be denser than the core. True or False? What is the primary disadvantage of pulse spreading in optical fibers? Why don't we see pulse spreading in single mode fibers? What is the difference between an isotropic antenna and an omnidirectional antenna? What factors determine antenna gain? Wireless transmission frequencies in the range of about 1 GHz to 40 GHz are referred to as frequencies. Highly directional beams are possible at these frequencies. A radio transmitter, has an output power of 0.5W and the transmitted carrier signal wavelength is 0.15 meters. The transmit antenna has a gain of lOdBi. Calculate the power received in dBm by an isotropic antenna at a distance of 200 meters