The prefix "poly-" means "many," and "atomic" refers to atoms, so a polyatomic ion is made of 2+ atoms covalently bonded together. These ions are charged, which is why they can never stand alone.
Answer:
When the red test lead is positive (+) and the black test lead negative (-), the meter will register voltage in the normal direction.
Explanation
12 Dahlias, 30 Tulips
12:30
12/2=6
30/6=5
12/6=2
=2:5
More the number of turns, more will be the magnetic field produced.
Hence wire A will have magnetic field greater than wire B.
Hope this helps!