Answer:
d) Wind
Explanation:
Secondary energy is energy produced by converting energy available in its natural state in the environment. Hence Wind is a primary source not a secondary source
It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
The answer is B) region of high pressure in a medium caused by a passing wave
Compression is the forcing of the molecules of a medium, be it water, air, or something else, as a wave passes by. This forcing together of the molecules raises the pressure of the medium in the area that the wave passes through.
Answer:
4.62 s
Explanation:
We are given that
Initial angular speed,



Substitute the values






Hence, the wheel takes 4.62 s to come to rest.
The Sun is a star around which our planet Earth and other planets and satellites of our solar system revolve along specific orbits. Sun appears to be spherical in shape and consists of glowing hot gases. It contains mostly hydrogen and helium gases. The temperature of the gas mixture is extremely high.
Therefore, the Sun mostly composed of hydrogen and helium gases.
(Answer) B. Composition mostly hydrogen and helium gas, Mass 1.989 x 10^30 Kg