explain each point in more detail please, im having a hard time understanding this. examples would be helpful!

Chapter 2 material (Measurements) - Know why the use of units is crucial in science. - Know how SI units work. - Know that gram (g) and kilogram (kg) are common units of mass. - Know that prefixes are attached to SI units to indicate multiplication by a power of 10 , e.g. 1 millimeter (mm) is 1/1000 of a meter or 103m. - Know how scientific notation works, and be able to convert a number from regular notation to scientific notation and vice versa. - Know how negative exponents work in scientific notation: 10n=1/10n. - Be able to use the rules of exponents and order of operations (PEMDAS) in arithmetic calculations. - Know that the SI unit of volume is m3, but that liters (L) and milliliters (mL) are much more common volume units in chemistry