Phân tích những dấu hiệu nhận biết sự phát triển du lịch bền vững về kinh tế.Tại sao dấu hiệu đó lại thể hiện sự phát triển du lịch bền vững về kinh tế

world war i had a devastating effect on german-americans and their cultural heritage. up until that point   german-americans, as a group, had been spared much of the discrimination, abuse, rejection, collective mistrust experienced by so many different racial and ethnic groups in the history of the united states. indeed, over the years, they had been viewed as a well integrated and esteemed part of american society. all of this change with the outbreak of war.  

answer; ///attempts to change more than once behavior at the same time;