The correct answer is D because the the rest will have different answers depending on the person you ask. D can be proven with facts by research
<u>Answer:</u> The electronic configuration of gallium is written below and number of valence electrons is 3.
<u>Explanation:</u>
Electronic configuration is defined as the representation of electrons around the nucleus of an atom.
Number of electrons in an atom is determined by the atomic number of that atom.
Valence electrons are defined as the electrons present in the outermost shell of an atom.
We are given:
An element Gallium having atomic number as 31.
Number of electrons = 31
Electronic configuration of Gallium is: 
This element has 3 electrons in its outermost shell. So, the number of valence electrons is 3
Hence, the electronic configuration of gallium is written below and number of valence electrons is 3.
B im just typing more because it has to be longer than 20 characters
Arrhenius concept just states that if a solution dissociates and forms H+ ions then its and acid, but if it dissociates and forms OH- than it's a base.
So the answer to your question would be D. An Acid
You can use the equation f(t) = 5*(1/2)^(t/8.02)
Then plug in 6.01 for time.There remains 2.97 mg in the sample.