I believe all of the anwers apply.
The 'fewer natural resources" is applicable assuming they are currently depleting their natural resources.
The effects of acid rain are most clearly seen in the aquatic, or water, environments. For an example, streams, lakes, and marshes.Acid rain flows to streams, lakes, and marshes after falling on fields, forest, roads, and buildings. Acid rain also directly falls on aquatic habits.
Answer: They are describing what kinds of cultures are in each place.
Explanation:
When geographers refer to describing places spatially, they describe what kids of culture are in each place.
Answer:
b. flat rotation curves in spiral galaxies
Explanation:
Dark matter accounts for majority of the matter in the universe (about 85%). It is considered to be composed of subatomic particles which are yet to be discovered. Dark matter cannot be observed because it does not emit light that can be detected. Only its gravitational effect is visible.
Astronomers when calculated the mass of the visible matter and tried to account for the observed speed of stars in the galaxy, there was a mismatch. To understand what caused this mismatch, astronomers gave name to the invisible matter as the Dark Matter.
The expected velocity of stars should decrease away from the near the center of the galaxy but a constant velocity of stars was observed that is a relatively flat rotation curve was obtained.
Thus, flat rotation curves in spiral galaxies in an evidence of Dark Matter.
Because with maps they knew where to go , without them they will be lost
