Question 2: The four children are 6 years old, 7 years old, 8 years old and 9 years old.
Question 3: The mass of a cubic decimeter object is 8g× 1000 ÷ 1000 = 8kg.
1T The volume of such an object is:1t ÷ 8kg ÷1000 = 0.125 (cubic meter).