Answer:
Hg Pb are in one, Li and B and O are in one, and NaCl are in one, As is alone
Explanation:
Periods are horizontal
Hope this helps!
Answer:
The filter bed is cleaned by occasional backwashing ;-; im sorry if this isn't a great answer but I tried
Answer:
I think the answers are... b, d, and maybe a. I don't know for sure. So only put these answers in if you trust me!
Explanation:
I had this very question, and I put in what I think were the answers.
