<span>So far, astronomers have found more than 500 solar systemsand are discovering new ones every year. Given how many they have found in our own neighborhood of the Milky Way galaxy, scientists estimate that there may be tens of billions of solar systems in our galaxy, perhaps even as many as 100 billion.</span>
Radio waves are electromagnetic waves and as such travel at the speed of light. Waves emitted a century ago would be 100 hundred light years away. A light year is the distance light travels in one year. In one year light travels about 5.9 trillion miles. therefore the waves traveled about 590 trillion miles in a century.
The Harappa’s system of standardized weights and measures signified advance technology and an advancing civilization in the Indus River Valley. Remarkable accuracy in systems and tools of the Harappan people were demonstrated by fire-baked bricks which were consistently moisture resistant and uniformly sized.
Erosion needs Earths rock
Erosion is wearing down and carrying away rocks by wind and moving water, happens faster with steep hillsides and heavy rain
I didn't understand the question
