Answer:
Water
Explanation:
Because it does not conduct much energy.
Answer:
Toward the centre of the circular path
Explanation:
The can is moved in a circular path: this means that it is moving by circular motion (uniform circular motion if its tangential speed is constant).
In order to keep a circular motion, an object must have a force that pushes it towards the centre of the circular trajectory: this force is called centripetal force, and its magnitude is given by

where m is the mass of the object, v its tangential speed, r the radius of the trajectory. This force always points towards the centre of the circular path.
The sum of all forces on an object is called the "net" force on it.
For an object at rest, we call that sum of forces "zero".
D is the answer! Hope it helps