question: According to Einsteins two relativity theories , the concept of time depends on what ?
answer: the spatial reference frame of the observer , and the human perception
turker_answer: According to Einsteins two relativity theories , the concept of time depends on the spatial reference frame of the observer , and the human perception .
rule-based: According to Einsteins two relativity theories , the concept of time depends on the spatial reference frame of the observer , and the human perception .