List kepler's laws and give a brief description of each law.

1) The law of orbits. This is when all planets move in elliptical orbits, with the sun at once focus.

2) The law of areas. A line that connects a planet to the sun sweeps out equal areas in equal times.

3) The law of periods. The square of the period of any planet is proportional to the cube of semimajor axis of its orbit. 

These laws were derived for orbits around the sun, but they apply to satellite orbits also. I hope this helps! ~Mia

answer: - b cells

explanation: -

there are many types of white blood cells present in our body. one such class of white blood cells are the lymphocytes. the b cells belong to the lymphocyte class of wbcs. the b cells perform their action against the pathogen by producing specialised proteins called as antibodies. these antibodies are produced as and when the b cells encounter pathogens in response to the antigens present on the surface of the pathogen. these antibodies bind to the antigens present on the pathogen and then, target them for destruction by other cells of the immune system.

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.