Why galaxy is called milky way?

Which of the following statements are correct?

(i) The Big Bang Theory attempts to explain the origin of universe.

(ii) In the solar system of the Milky Way galaxy, earth was formed about $4.5$ billion years back.

(iii) Oparin of England and Haldane of Russia proposed that the first form of life could have come from pre–existing non–living organic molecules.

(iv) In$1963, S. L.$Miller, an American scientist, gave experimental proof of the Oparin–Haldane hypothesis.