How do you convert 642cg to kilograms

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution? a. 3.88 m, b. 1.03 m, c. 1.5 m, d. 15.5 m

One way that radioactive waste is treated is by burying it in repositories. the repositories are found only in states with very low populations. true or false? a. trueb. false(also i meant to put high school but it put down middle school instead)

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world