Electromagntic wave, such as an X-ray.
Explanation:
- Electromagnetic wave does not require any medium to travel. These waves propagate outwards from the source.
- They can travel even through the vacuum of outer space.
- The major source is the sun which emits radiation in the form of the Electromagnetic spectrum.
- These waves travel through oscillating electrical and magnetic fields generated by the oscillating charged particles.
- These waves oscillate in the perpendicular direction of planes concerning each other and are in form.
- Electromagnetic waves travel at speed of light.
Answer: 1917, two revolutions swept through Russia, ending centuries of imperial rule and setting into motion political and social changes that would lead to the formation of the Soviet Union.
Explanation:
A person with a disability can look to the government for help. The government provides a social security fund for people unable to work due to a disability. The answer is true.
Answer:
The Hadean eon represents the time interval between 4.6 billion to 4 billion years back. It is marked by the initial formation of the earth , right from the time of gathering and accumulation of interstellar dust particles and gases, and there was frequent collision between the planetesimals of relatively larger in size. The core and the crust formed and started to become stable and also gradually led to the formation and expansion of the ocean and the earth's atmosphere.
This is how the earth gradually started to form and develop and took the shape during the time interval between 4.6 billion to 4.2 billion years old, and where the oldest rocks found on earth is dated from about 4.2 billion years in the past.