教甄◆英文科題庫下載題庫

        In 1892, a resident with cholera accidentally __(11)__ the disease via the Elbe River to Hamburg, Germany's entire water supply. Within weeks, ten thousand citizens died. Eight years earlier, German microbiologist Robert Koch had made a discovery: cholera was__ (12)__. Koch's revelation__(13)__ officials in large European cities to invest in filtration systems to protect their water. Hamburg authorities, __ (14)__, had done nothing. Citing costs and alleging dubious science, they'd ignored clear warnings while their city__(15)__ toward catastrophe.