The genetic material appearing like a thread in the nucleus is known as

Which of the following is not a possible effectof increasimg carbon dioxide levels in the atmosphere ?

Which of the following forest management practices is best for reestablishing areas of forest?

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?