What does the associated graph indicate about a stream?

A. Silt and clay are carried in suspension under most stream velocities.

B. Sand and gravel are deposited at low velocities but transported at higher velocities.

C. Sand is carried in suspension only at high velocities.

D. As fast-moving water slows down, fine sand can switch from transport by suspension to the bed load.

E. All of these.

Which would cause the aggregate demand curve to decrease, ceteris paribus?

Why would a decrease in the density of the ozone layer in Earth's atmosphere cause public health problems?

What is the difference between a meandering stream and a braided stream?

A. A braided stream has a high sinuosity (lots of bends) and a meandering stream contains a network of branching channels. Braided streams are usually steeper and shallower than meandering streams.

B. A meandering stream has a high sinuosity (lots of bends) and a braided stream contains a network of branching channels. Braided streams are usually steeper and shallower than meandering streams.

C. A braided stream has a high sinuosity (lots of bends) and a meandering stream contains a network of branching channels. Meandering streams are usually steeper and shallower than braided streams.

D. None of the above

Which event is best represented by the hydrograph shown here?

A. a summer thunderstorm

B. a very long period of steady light rain

C. a long drought with no rain for months

D. a winter snowstorm followed by very cold weather

Describe the character of meander scars and oxbow lakes on the floodplains of meandering rivers.

Which of the following is unlikely to cause deposition of sediment along a stream?

A. a decrease in gradient

B. a decrease in water velocity

C. a drop in sea level

D. none of these

Which of the following events would cause an increase in aggregate demand?

a. A decrease in consumption

b. An increase in taxes

c. A decrease in price level

d. A decrease in taxes

What could cause this stream to deposit sediment?

A. a rise in base level, such as a rise in sea level

B. subsidence of the land, producing slopes that are less steep

C. both a rise in base level or subsidence of the land

D. none of these

Where would be the relatively safest place to build a bridge across the stream in the accompanying figure?

A. between points 1 and 2

B. between points 3 and 4

C. between points 5 and 6

D. between points 7 and 8

Which of the following is NOT true about braided streams?

A. these streams form where the sediment is plentiful and dominated by clay and silt

B. the amount of sediment is close to or exceeds the stream's capacity to carry it

C. more than one channel can carry water and sediment

D. they can have a fairly straight overall path or gentle curves

In the accompanying hydrograph for major river, a flood was caused by a single episode of heavy rainfall 50 kilometers upstream. When did the rain most likely occur?

A. at time $A$

B. at time B

C. at time $C$

D. at time D

Which of the following sites is most likely to be flooded if all other factors are held constant?

A. a site that is higher but closer to the river than a site that is lower but farther from the river

B. a site next to the river where the main channel is wider and deeper than other segments of the river

C. a site on the floodplain instead of a site on an older terrace

D. all of these

Which of the following is true about a delta?

A. A delta forms as channels merge and pile up sand.

B. A river keeps forming a delta in the exact same position along a coastline.

C. Deltas form some layers that are horizontal and form some that are inclined toward the ocean.

D. The total amount of sediment carried by the river increases from the start to the end of the delta system.