Question

if more rain falls into a stream during a year than in previous years, how might the stream change?
a. faster flowing water from upstream will deposit more sediment near the edges of the stream. the stream will appear more narrow.
b. faster flowing water will erode more of the loose soil from the edges and bottom of the stream. the stream will appear to get wider and deeper over the year.
c. more water in the stream will weather and break down nearby rocks, causing broken rocks to fall into the stream. the stream will appear more shallow over the year.
d. more water in the stream will lead to larger areas of water freezing in the winter. the frozen water will push along the sides of the stream. the stream will appear to change direction over the year.

Explanation:

To solve this, we analyze each option:

• Option A: Faster - flowing water (from more rain) typically erodes, not deposit, sediment near edges. Deposition usually occurs in slower - moving water. So A is incorrect.
• Option B: When there is more rain, the stream has more water, which flows faster. Faster - flowing water has more erosive power. It can erode the loose soil from the edges and the bottom of the stream. As the soil is eroded, the stream will become wider (from eroding the edges) and deeper (from eroding the bottom) over time. This is consistent with the processes of stream erosion.
• Option C: While water can weather rocks, the broken rocks falling into the stream would make the stream deeper, not more shallow. So C is incorrect.
• Option D: The idea that frozen water would push the stream to change direction is not a typical or accurate process related to increased rainfall in a stream. Stream direction is mainly determined by the topography of the land, not the pushing of frozen water. So D is incorrect.

Answer:

B. Faster flowing water will erode more of the loose soil from the edges and bottom of the stream. The stream will appear to get wider and deeper over the year.