Density is related to weight and box measurements. Since the box is the same only factor changing the density of the box is the weight of what’s in it. Box with marbles has the greatest density
Answer: 6.313 miles
Explanation:
The distance is calculated by Simple Rule of Three:

the nuclear stockpile of the United States peaked in 1967
Answer:
America was reorganized around a system of highways that had their own language.
Explanation: At the same time, the interstates also made travel in and out of American cities easier which speeded the growth of the suburbs.