Population control factors whose effects increase as the size of the population increases are

Eristics do scientists use to distinguish between organisms in different kingdoms

In which squares should the phrase "green pods" appear a) a and d b) b and e c)a,c, and d d)a,b,c,d and e

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?