I would say B but I have no clue
I think the correct answer would be D. The tap water in the experiment is one the three test conditions of the independent variable, the type of water. The independent variable in a experiment is the one being manipulated or the one being changed. In this case, it is the type of water.
Under water turbans that are placed at the above to middle of the ocean they are used to capture kinetic motion
Option A, current (thumb) to magnetic field (fingers)
As per the First right-hand rule,
Using right hand, if we suppose that thumb points towards the electric current
fingers curl towards the magnetic field
Answer:
Atomic number of calcium is 20.