If the force moving an object points at least partially in the opposite direction of the objects motion the work is considered to be what

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

measure their densities same density, same sub