Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores. Aside from our sun, the dots of light we see in the sky are all light-years from Earth. They are the building blocks of galaxies, of which there are billions in the universe. It’s impossible to know how many stars exist, but astronomers estimate that in our Milky Way galaxy alone, there are about 300 billion.
Explanation:
6000 years = 6000 x 365 x 24 x 60 x 60
= 1.892 x 10¹¹ second
gain is 1 second
1 second is equivalent to 9.193 × 10⁹ oscillations .
In 1.892 x 10¹¹ second , change in oscillation is 9.193 × 10⁹ oscillation
in one second change in oscillation = (9.193 / 1.892 ) x 10⁹⁻¹¹
= 4.859 x 10⁻² oscillations .
Displacement is usually how the messure the rock
The decimal point is placed after two digits starting from the end. For each decimal place, we can write the number divided by 100.
21.12 can be written as 
.
Divide the numerator and denominator by 2:
The numerator and denominator can be divided by 2 again:
There is no other common factor between numerator and denominator other than 1. Hence, it is the reduced form.
the polluted urban environment affects the health and quality of life
