What were likely evolved directly from fro-magnons

As soon as possible this assignment is due in 5 minutes atoms in a molecule are bonded together by sharing, gaining, or a. photons b. protons c. neutrons d. energy f. electrons

Average annual precipitation and are the two major features that define the biomes on earth.

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?