What are freshwater ecosystems with high biodiversity that are also declining in numbers
a. lakes
b. oceans
c. wetlands
d. rivers

im back lol i heard you where asking for me

idk why hjggjhjkhj

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.