The system includes the lungs. a. endocrine b. immune c. respiratory d. circulatory

C. respiratory

Explanation:

The lungs are the vital organs which are the part of the respiratory system. A respiratory system consists of specialized organs both in plants as well as in animals which helps in the process of exchange of gases. The two lungs consists of network of blood vessels and tubes where gaseous (carbon dioxide and oxygen) exchange takes place. The tubes and blood vessels includes the brochioles, the alveoli and the capillaries. The oxygenated blood from the lungs is transported to heart for circulating it to all the parts of the body.  

answer by yourhope:

hi! : )

in which structure in the nucleus are ribosomes made?

b) nucleolus!

: )

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy