Answer: 
Explanation:
The Tropic of Cancer is one of the parallels (imaginary line around the Earth parallel to the equator) located in the northern hemisphere (currently its latitude is 
).
It is called "Cancer" because a long time ago, when the summer solstice occurred in the northern hemisphere (on June 20th or 21st), the Sun was in the constellation Cancer (the crab).
Now, if we were just in the North Pole, Polaris would by exactly over our heads (
over the horizon), but as we go south and find the Tropic of Cancer parallel, Polaris altitude will be approximately at an angle of over the horizon.
Hence, the altitude of Polaris measured by an observer at the Tropic of Cancer is .
Answer:
According to one estimate, stands of century-old forest now account for only 7% of forest cover in the United States (USDA-FS 2000). Since 1600, 90% of the virgin forests that once covered much of the lower 48 states have been cleared away.
Explanation:
Mount Baker-Snoqualmie National Forest, Washington
The Mount Baker-Snoqualmie forest is located in the Cascade mountain range in Washington state and is home to 644,000 acres of old-growth. Situated around an hour away from the Seattle metropolitan area, this forest is one of the most frequently visited in the country.
1-choose any two points on the line.
2-draw a right-angled triangle with the line as hypotenuse.
3-use the scale on each axis to find the triangle's: vertical length.horizontal length.
4-work out the vertical length ÷ horizontal length.
5-the result is the gradient of the line.
The answer for "What is petrified wood made of?" would be minerals.
