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The least penetrating form of radiation is

Find the dimensions and area of the largest rectangle that can be inscribed in the upper half of the ellipse. (give your answers in terms of a and b. enter the dimensions as a comma-separated list.)

Would it be correct to say the doppler effect is the apparent change in the speed of a wave due to the motion of the source? be sure to fully explain your position using at least 3 complete content related sentences.