Na2SO4(aq) + CaCl2(aq) — CaSO4(s) + 2NaCl(aq) Ionic Equation:
2Na+ (aq) + S02-(aq) + Ca2+(aq) + 2C1- (aq) —>
CaSO4(s) + 2Na+ (aq) + 2Cl- (aq)
Recall that spectator ions are ions present in
solution that do not participate directly in the
reaction. What are the spectator ions in this
reaction?
A. Ca2+ and SO2- B. Na+ and SO2-
C. Na+ and CI-
D. Ca2+ and CI-

I have no idea what any of this means

Explanation:

give brainliest

water pollution kills aquatic life. aquatic life includes algae and other plant life that use photosynthesis. photosynthesis takes   c02 out of the air.  

c02is a greenhouse gas.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.