After a cs comes to elicit the cr, the cs now can be paired with a new neutral stimulus and this second neutral stimulus will start to elicit a cr. this process is called

answer; 5,000 to 100.000 typical is the minimum coverage,now every state is different;

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there is no universally accepted definition of art. although commonly used to describe something of beauty, or a skill which produces an aesthetic result, there is no clear line in principle between (say) a unique piece of handmade sculpture, and a mass-produced but visually attractive item. we might say that art requires thought - some kind of creative impulse - but this raises more questions: for example, how much thought is required? if someone flings paint at a canvas, hoping by this action to create a work of art, does the result automatically constitute art?