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If it takes a planet 2.8 x 10^8 s to orbit a star with a mass of 6.2 x 10^30 kg what is the average distance between the planet and the star

Three charge are arranged as shown in the diagram. the magnitude of the net electrical force acting on the +6 uc charge, rounded to the tenths place, is .

The vapour pressure of benzene is 53.3 kpa at 60.6 °c, but it fell to 51.5 kpa when 19.0 g of a non-volatile organic compound was dissolved in 500 g of benzene. calculate the molar mass of the compound.