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OMG PLEASE HELP ME!! ITS QUICK! CALC QUESTION? Verify the identity cos(2x)/sin(2x)+2sin^2(x)=1/2(cot(x)-1). Need help? Under constant temperature, a pressure of 12 torr and a volume of 8 L, what is the
new pressure if the volume decreased to 6 L? How many moles of PbCl2 will dissolve in 1.0 L of 0.051 M NaCl solution. how do i do this? How are elements grouped according to the number of valence electrons in their outermost levels?