If a scientist found a sample of crystal, which had a large amount of
lead surrounding it, how would you describe the age of this crystal? Very young, old, or is the amount of lead not related to the age?

I believe the lead would not matter to the age

tropical storm katrina, and it made landfall between miami and fort lauder-dale, florida, as a category 1 hurricane (a storm that, on the saffir-simpson scale, exhibits winds in the range of 74–95 miles per hour [119–154 km per hour]). sustained winds of 70 miles per hour (115 km per hour) lashed the florida peninsula, and rainfall totals of 5 inches (13 cm) were reported in some areas. the storm spent less than eight hours over land. it quickly intensified when it reached the warm waters of the gulf of mexico.

this should answer you're question

d. stage 4

explanation:

the existence of some kind of demographic transition is widely accepted in the social sciences because of the well-established historical correlation linking dropping fertility to social and economic development.[1] scholars debate whether industrialization and higher incomes lead to lower population, or whether lower populations lead to industrialization and higher incomes. scholars also debate to what extent various proposed and sometimes inter-related factors such as higher per capita income,lower mortality, old-age security, and rise of demand for human capital are involved.[2]