Which of the following is an example of how cities responded to public health and sanitation issues?
a. the publication of muckraker journals
b. the creation of open sewer systems
c. the chlorination and purification of drinking water
d. the establishment of tenement housing

The rich natural resources made the sacramento valley a "garden of eden." permanent villages were established about 8,000 years ago.which choice combines these two sentences from paragraph two to achieve a coherent flow of ideas? a) the rich natural resources made the sacramento valley a "garden of eden" and permanent villages were established about 8,000 years ago. b) permanent villages were established about 8,000 years ago and the rich natural resources made the sacramento valley a "garden of eden." c) the rich natural resources made the sacramento valley a "garden of eden; " and so the permanent villages were established about 8,000 years ago. d) because of the rich natural resources which made the sacramento valley a ‘garden of eden,’ native americans established permanent villages there 8,000 years ago.