IT IS D FOCAL POINT
P.S. im in middle school not trying to brag
its A. Genes make up chromosomes. it did it on study island..... i did the other answer the other person got and i got it wrong....and then it told me it was A. Genes make up chromosomes.
HOPE I COULD HELP
Answer:
The scientific method is a system of reasoning. You can make reasonable explanations for something that you are observing in the world.
Explanation:
Answer:
All elements in the same group of the periodic table have the same number of valence electrons. This made it possible to compare the valence of the alien elements to the valence of elements from our periodic table, and match the alien elements to the correct group. For example, our group 14 elements all have 4 valence electrons, so the alien element with 4 valence electrons had to be part of group 14 also.
Can't say i can answer this. :/