To calculate the density, we must first calculate the volume of the object. For a rectangle, the volume is equal to V=l*w*h. In this case, V=22*13.5*12.5=3712.5 mm^3. Next we have to convert the mm^3 to mL using the conversion factor of 1 mm^3=.001 mL. To get mL, we set up the expression 3712.5 mm^3 * (.001mL/1mm^3) = 3.7125 mL. Finally, to get the density, we know density is mass over volume, so we set the expression p=m/V=2.5g/3.7125mL=.6734 which rounded to 3 significant figures is .673. The answer will be .673
