The correct answer to the question is A) Electrons.
EXPLANATION:
The electrical conductivity of a metal or any substance depends on the free electron concentration of the metals.
Free electrons are those electrons which are present in the conduction band of the metals. These electrons experience less amount of force attraction from the nucleus. Protons and neutrons do not contribute anything to the current conduction in a metal.These sub atomic particles are bound to the nuclei of atoms.
When we maintain potential difference across the two ends of a conductor, the free electrons are drifted towards the positive terminal of the battery.
Hence, electrical conductivity of a substance is the ability of the electrons to move inside the substance.
More is the conductivity of the substance, the lesser is the resistance to the flow of electrons inside the substance, and vice versa.
C. When ever it comes to questions like these, I like to think of a seesaw with a huge amount of weight on one end. Which position would work best for that? With the effort arm being longer, you have more leverage so the load arm will move easier.
Answer:
Electric field, 
Explanation:
It is given that,
Charge, Q = +6.1 C
Distance, r = 21 cm = 0.21 m
We need to find the electric field. It is given by :



So, the electric field at this distance is
. Hence, this is the required solution.
Answer: Radiation
Explanation:
There are three ways in which the thermal transfer occurs:
1. By Conduction, when the transmission is by the <u>direct contact</u>.
2. By Convection, heat transfer <u>in fluids </u>(like water or the air, for example).
3. By Radiation, by the <u>electromagnetic waves</u> (they can travel through any medium and in <u>vacumm</u>)
So, in the outter space is vacuum, this means the energy cannot be transmitted by convection, nor conduction. It must be transmitted by electromagnetic waves that are able to travel with or without a medium, and this is called radiation.
Answer:
it's pray hoped this helped