[amp_mcq option1=”Only III” option2=”Only I and III” option3=”Only II” option4=”All are correct” correct=”option1″]
The correct answer is: Only III.
A parsec is a unit of astronomical distance equivalent to about 3.26 light-years, or 30.86 trillion kilometers (19.18 trillion miles). It is used to measure the distance to stars and other objects outside the solar system.
A barrel is a unit of capacity or volume that is used to measure liquids and dry goods. It is equal to 42 gallons in the United States and 36 imperial gallons in the United Kingdom.
A light-year is a unit of astronomical distance equivalent to the distance that light travels in one year, which is about 9.46 trillion kilometers (5.88 trillion miles). It is used to measure the distance to stars and other objects outside the solar system.
Of the three pairs, only light year and time are incorrect. A light year is a unit of distance, not time.