Looking at the data in the text, we can see that the diameter of the Sun is about 100 times that of Earth, about 1,500,000 km for the Sun compared to about 12,000 km for Earth. A galaxy such as the Milky Way is about 100,000 light-years in diameter. Since a light-year is about 10¹³ km, this means the Galaxy has a diameter of approximately 10¹⁸ km, or about 10¹⁴ times (100 million million times) the radius of Earth. The most distant objects visible define the limits of the visible universe (which is likely only a small part of the entire universe). These objects are about 10 billion light-years away, or 10²³ km. This is 10¹⁹ times (10 billion billion times) the radius of Earth.
The answer to this question is C. the size of the rock's crystal. Rapid cooling results small crystals forming while larger crystals form when cooling occurs slowly.
