Which of the following is an example of reproductive isolation?

a two populations of finches that cannot produce viable offspring
b two populations of finches that have different feather colors
c two populations of salamanders that live in different lakes
d two populations of salamanders that have different tail lengths

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?

Abody cell has been growing and at synthesis proteins. in the nucleus of this body cell, dna replication is taking place. and a copy of the cells genetic material is copied. which of the following is the best conclusion you can make about the life cycle of this cell ? a) the cell is ready to undergo mitosis. and a chemical signal will send the cell to prophase b)the cell is undergoing meiosis and will cross over the genetic material next c)the cell is in the s phase of interphase and will move next to the g2 phase d) the cell is in the g2 phase of the interphase and is ready to begin diving

What is gene flow? apexa: selection for average traits b: when a population splits in twoc: a mutation becoming more commond: genes moving between two populations