IV. Write the letter of the best answer before the number on your paper.
38. Whet ne river meets the sea, the two main properties of water that are affected are
a. salinity and pH
c. temperature and pH
b. salinity and temperature
d. temperature and dissolve oxygen
39. What causes the changing salinity of water in estuaries?
a. the amount of sunlight
c. the continuous flow of fresh and saltwater
b. the hotness and coldness of water
d. the kinds of rocks found in the estuary
40. What is the term for a sequence showing the feeding relationship between organisms in an
ecosystem.
a. food web
b, food chain
c. food supply d, food phyramid​