The water cycle is the

• distribution of drinking water on Earth.

• unending circulation of Earth’s water supply.

• the recycling of water after industrial use.

• the evaporation of water from Earth’s surface.

Balance in the water cycle means that

• the average annual precipitation over Earth equals the amount of water that evaporates.

• water that falls to Earth only enters oceans.

• the amount of water that falls to Earth weighs the same as the amount that condenses in clouds.

• water that evaporates from Earth’s surface remains forever in the atmosphere.

The ability of a stream to erode and transport material depends largely on its

• width.

• density.

• velocity.

• length.

A stream’s discharge

• decreases between its source and mouth.

• remains the same throughout its course.

• is greatest during times of drought.

• increases between its source and mouth.

Base level is

• the lowest point to which a stream can erode its channel.

• any part of the stream that is below sea level.

• the source from which the stream flows.

• the elevation of a stream’s largest tributary.

Most streams carry the largest part of their load

• as dissolved material.

• on their surface.

• as bed load.

• in suspension.

A depositional feature that forms where a stream enters a lake or an ocean is a

• natural levee.

• meander.

• delta.

• distributary.

The most prominent features of a narrow V-shaped valley where the stream profile drops quickly are

• meanders and floodplains.

• rapids and waterfalls.

• lakes and ponds.

• deltas and natural levees.

A floodplain forms where a stream

• cuts downward rapidly.

• is far above its base level.

• cuts mainly side to side.

• carries no bed load.

One major cause of floods is

• rapid spring snowmelt.

• a decrease in stream discharge.

• light rain over a large area.

• increased capacity of stream channels.