Plz help ive been stuck on this for 30 mins

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Animals that have thick fur and ae able to store large amounts of body fat live where ?