B. 18 though now I believe it’s 17
Answer:
The angle's rate of change is: -0.125 (degree/feet).
Explanation:
In this case of problem we need to find the angle's rate (α) of change when x=6 ft. First we need to relate (α) with x and y and the expression that do it is: 
where (α) is the angle between the ladder and the ground, x is the horizontal distance and y the vertical distance, now we need to have the variable y at function of x, so we can do it using the Pythagorean theorem and gets:
solving for y(x) we get:
. Replacing all we have got in the first equation: 
. Finally we derivate this equation at function of variable x and gets this result:
evaluating at x=6 ft we get: -0.125(degree/feet). The negative signal means that the angle is decreasing.
Answer:
b. during the final stages of cooling, a lava flow contracts, forming tall polygonal fractures
Explanation:
The columnar joints are very interesting and attractive for the eye geological features. They are not very common feature which makes them even more interesting. Some of them have been covered by sediments so they are hidden below the surface, but some have remained above the surface, sticking out as the erosion acts much slower on them than the surrounding area. They form when the lava cools off very quickly at its final stages, thus starting to contract, and instead of being smooth, they become polygonal fractures that are very tall.
<span>It's continuous except for a pair of dark lines.
They are very close together in the yellow/orange section of the spectrum.</span>
Answer:
3000J
Explanation:
The gravitational energy for any object is given by E=mgh
where m is mass, g is gravitational field strength anf h is height above ground
