Question

Can anyone help me out real quick

Answer 1

The conversion only gets tricky with the cubed labels.  Keep in mind that cm^3 is cm*cm*cm, and that m^3 is m*m*m, AND that there are 100 cm in 1 meter.  Here's how the conversion will look if we expand it to make it simple to understand: $2.5 \frac{g}{cm^3} * \frac{1kg}{1000g} * \frac{x100cm*100cm*100cm}{m*m*m}$.  If we do all that multiplying and dividing, and all the crossing out of the labels that cancel, we get $2500 \frac{kg}{m^3}$.  There you go!