Answer:
The correct answer is option B. coal
Explanation:
Coal is made of remains of organic material including trees and other vegetation which got trapped beneath the earth’s surface or at the bottom of the swamps. After burial below the ground the organic material was acted upon by the high temperature and pressure in the absence of air to form peat. Peat after further processing for a longer period of time converted into coal
Answer:
Volcanic activity is widespread over the earth, but tends to be concentrated in specific locations. Volcanoes are most likely to occur along the margins of tectonic plates, especially in subduction zones where oceanic plates dive under continental plates. As the oceanic plate subducts beneath the surface, intense heat and pressure melts the rock. Molten rock material, magma, can then ooze its way toward the surface where it accumulates at the surface to create a volcano. Volcanic activity can be found along the Mid-ocean ridge system as well. Here, oceanic plates are diverging and magma spreads across the ocean floor, ultimately being exposed at the surface. Crustal spreading long the ridge is partly responsible for the volcanic activity of Iceland. It is also thought that a "hot spot" lies beneath the island that contributes to volcanism.
Answer:
a. Speed = 342.5 meters per seconds.
b. Wavelength = 2.0 meters
Explanation:
Given the following data;
Distance = 100m
Time = 292 milliseconds to seconds = 292/1000 = 0.292 seconds
Frequency = 171 Hz
a. To find the speed of sound in air;
Speed = distance/time
Speed = 100/0.292
Speed = 342.5 m/s
b. To find the wavelength;
Wavelength = speed/frequency
Wavelength = 342.5/171
Wavelength = 2.0 m
First of all, you didn't tell us WHO measured the "10 years".
If it was the people on Earth, then 10 years passed according to them.
If it was 10 years on the space traveler's clock, then the clock in the
OTHER place, like on Earth, is subject to the relativistic 'time dilation'.
If the clocks are moving relative to each other, then the time interval measured
on either clock is equal to the interval measured on the other clock, divided by
√(1 - v²/c²) .
You said that v/c = 0.85 .
v²/c² = (0.85)² = 0.7225
1 - v²/c² = 1 - 0.7225 = 0.2775
√(1 - v²/c²) = √0.2775 = 0.5268
If one clock counts up 10 years, then the other one counts up
(10years) / 0.5268 = <em>18.983 years </em>
I believe that's the way to do this, and I'll gladly take your points,
but let me recommend that you get a second opinion before you
actually take off on your 10-year interstellar mission.
