Which may have been a reason for the decline of civilization in the indus valley? a. disease destroyed much of the population. b. major sandstorms destroyed the crops. c. craftsmen and laborers could no longer make a living.

Who ever answer first get ! question 1: which term names the outer edge all around a watershed? a. divide b. basin c. boundary d. collection area question 2: which feature does contour line indicate on a topographic map? a. the path of a river through the watershed b.equal elevation c. similar runoff level d. the boundary of an aquifer