Answer is: A) Sr (strontium).
The reactivity series<span> is a series of metals from highest to lowest reactivity.</span><span> Metal higher in the reactivity series will displace another.
</span>Strontium is only higher in this group from magnesium. Strontium is stronger reducing agent than magnesium, gives electrons easier.
The atomic number of an element gives the proton and electron in the atom while the mass number gives the total number of protons and neutron
<span>the Brazil Current has the warmest water</span>
The correct answer is b. an element
The explanation:
when the ELEMENT is define as substance that cannot be decomposed (broken down) into simpler substances by ordinary chemical means. Examples: gold, iron, carbon, hydrogen, oxygen, nitrogen
Ex: diamond will be broken into carbon as well.
and SUBSTANCE: Material composed of only one kind of matter throughout (same atoms or same molecules).