Answer:
Valence
Explanation:
In an atom, the electrons at the outermost energy level is called as valence electrons. It is the valence electrons which participates and interacts with the other atoms and form bonds. The valence electrons of an atoms are important as they depict the chemical properties of an element.
Thus the valence electrons resides the outermost shell and surrounds the atomic nucleus.
Answer:
Explanation:
A convex lens acts a lot like a concave mirror. Both converge parallel rays to a focal point, have positive focal lengths, and form images with similar characteristics. A concave lens acts a lot like a convex mirror.
I am thinking the rock that forms from lava that cools quickly is D) Obsidian.
Answer:
C
Explanation:
The brother has different alleles for the blood type gene than his sister does. Blood type is inherited from parents like many other traits that can be displayed on a punnet square. Depending on what the parents blood type alleles were, the brother and sister could have different blood types.
A different number of chromosomes doesn't lead to different blood types, so D is wrong. And A is incorrect because the number genes also does not affect blood type. And I think the blood type genes are on the same chromosome, so B is wrong. C is correct because blood type is inherited by alleles, and different alleles can cause different traits, such as blood types.