Educational worksheet showing a cross-section of a watershed with labels for various components and multiple-choice questions.

Problem Analysis:

The image provided is a diagram of a watershed, and the task involves answering questions related to watersheds based on the diagram and general knowledge. Let's solve each question step by step.

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Question 1: One watershed is separated by which geographical feature?

- Options:
- a. Mountain
- b. Valley
- c. Ocean
- d. River

#### Explanation:
A watershed is an area of land where all the water that falls on it (rain, snow, etc.) drains into a common body of water, such as a river, lake, or ocean. Watersheds are typically separated by natural barriers like mountains or ridges, which act as divides preventing water from one watershed from flowing into another.

#### Answer:
a. Mountain

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Question 2: What force causes water to flow through a watershed?

#### Explanation:
Water flows through a watershed due to the force of gravity. Gravity pulls water downhill, causing it to move from higher elevations (such as headwaters) to lower elevations (such as rivers, lakes, or oceans).

#### Answer:
Gravity

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Question 3: As you travel in a watershed from the headwaters to the outlet, the elevation will ________ and the size of the tributary will ________?

#### Explanation:
- Elevation: Headwaters are typically located at higher elevations (e.g., mountainous regions). As water flows downstream, it moves toward lower elevations.
- Size of the tributary: Tributaries are smaller streams that feed into larger rivers. As water flows downstream, multiple tributaries merge, increasing the size of the main river.

#### Answer:
As you travel in a watershed from the headwaters to the outlet, the elevation will decrease and the size of the tributary will increase.

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Question 4: Which watershed is all of Lancaster County a part of?

- Options:
- a. Landis Run Watershed
- b. Conestoga River Watershed
- c. Chesapeake Bay Watershed

#### Explanation:
Lancaster County is located in Pennsylvania, USA. The entire county is part of the Chesapeake Bay Watershed, which is a large drainage basin that includes parts of six states and the District of Columbia. While Lancaster County may have smaller sub-watersheds (like the Landis Run Watershed or Conestoga River Watershed), it ultimately drains into the Chesapeake Bay.

#### Answer:
c. Chesapeake Bay Watershed

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Final Answers:

1. Mountain
2. Gravity
3. Decrease, Increase
4. Chesapeake Bay Watershed

Boxed Final Answer:
\[
\boxed{\text{1. Mountain, 2. Gravity, 3. Decrease, Increase, 4. Chesapeake Bay Watershed}}
\]