Hubble's law states that the velocity with which a galaxy is moving away from the Earth is proportional to:

The galaxy in which we live is:

$A$ galaxy is observed to be moving with a velocity of $8600 \ km \ s^{-1}$. If it is at a distance of $430$ million light-years from us,the Hubble constant and the corresponding age of the universe are respectively:

The farthest objects in our Universe discovered by modern astronomers are so distant that light emitted by them takes billions of years to reach the Earth. These objects (known as quasars) have many puzzling features,which have not yet been satisfactorily explained. What is the distance in $km$ of a quasar from which light takes $3.0$ billion years to reach us?

The image shows a diagram of the solar system. Which of the following correctly identifies the planets in the order of their distance from the Sun?

$A$ Black Hole is: