At which instance contain 1 molecule of substances from following? (1). Hydrogen atoms of 2g of Hydrogen
(2). Oxygen atoms of 8g of Oxygen
(3). Water molecules of 8g of water
(4). Methane molecules of 16g of methane

I think it is 1 hydrogen sorry if I’m not right

The answer is ozone layer.

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.