Also known as segmented worms, have a closed circulatory system.

The answer is joseph is observing the colour of the reaction mixture to see whether proteins are present in the given solution.

Lipid because of the high percentage of carbon to carbon bonds, which store more energy than other bonds.

It depends on the surface of the levels. the rougher the surface, the greater is the frictional force. for rougher surfaces, you would need to exert greater force to move the object. the concept is that, you must overcome the frictional force in order to bring the object into motion. this is the reason why we add lubricants to the joints so they could easily move. this answer was on