What events in the history of mankind have to propel our species

When lactate builds up in a runners muscles it causes a burning sensation what causes this to occur

Can someone pretty me with this ? it’s urgent.compare the three theories of emotion. here are the three theories of emotion. cannon-bard theory of emotion: the belief that both psychological arousal and emotional experience are produced stimultaneously ( at the same time) by the same nerve stimulus. james-lange theory of emotion: the belief that emotional experience is a reaction to bodily events occurring as a result of an external situation. ( “ i feel sad because i am crying.) schachter-singer theory of emotion: the belief that emotions are jointly determined by a nonspecific kind of psychological (bodily function) arousal and its interpretation, based on environmental ( natural surroundings) cues. which of these theories makes most sense to you? why. your response should be written using proper english spelling and grammar. and it needs to be 10 complete sentences.

Which of your fossils are most likely heterotrophs? which of them are autotrophs? how do you know?