Answer:
i would say D i just did this but i kinda forgot so sorry if im wrong or A
Explanation:
Lead.
Lead paint was a big problem and now lead has been removed from paint because it was found to be dangerous to the health of living organisms.
Hope this helps! :)
Answer:
Rb: [Kr] 5s
Step-by-step explanation:
Rb is element 37, the first element in Period 5.
It has one valence electron, so its valence electron configuration is 5s.
The noble gas configuration uses the symbol of the previous noble gas as a shortcut for the electron configurations of the inner electrons.
The preceding noble gas is Kr, so the electron configuration is Rb: [Kr] 5s.
As the building blocks of proteins , amino acids are linked to almost every life process, but they also have key roles as precursor compounds in many physiological processes.