Find the volume of 15.2 ml - 10.8 ml using the correct significant figures

Which statement is true about ionic compounds?

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

Which is an example of a highly unstable isotope that is often used in fission reactions?