One type of board routinely used to build microwave circuits is 50-mil-thick Rogers Corporation RT/Duroid, with εᵣ =10.8 and tanδ=0.0028. It is coated on both sides by " 1/4 oz copper." This translates to a 0.35 -mil thickness of copper. Find w and uₚ for a 50−Ω line. Then determine the α, α, and αₜₒₜ at three frequencies: 1, 10, and 20GHz. What is the maximum frequency of operation for this microstrip?