Humans burn fossil fuels and wood, releasing carbon dioxide into the atmosphere. This carbon dioxide is then absorbed by trees for photosynthesis. These processes are contributory to which chemical cycle?

Acertain species of fish can have either long or short fins. the allele for long fins is dominant over the allele for short fins. a heterozygous, long-finned fish is crossed with a homozygous, short-finned fish. of the offspring, will have long fins and be , and will have short fins and be .

Pink fur (p) is dominant to purple fur (p) in hamsters. two heterozygous pink hamsters are crossed. what is the probability that these two parents will have an offspring with purple fur? 2/4, 1/2 or 50% 1/4 or 25% 3/4 or 75% 4/4 or 100% there is no chance for this type of offspring

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?