1) Refraction
2)Reflection
3)Concave
4)Convex
I took the test and got this right so you can believe me :)
Hope this helps
Answer:
Explanation:
Electrical energy is energy derived from electric potential energy or kinetic energy.
Or,
Electrical energy is a form of energy resulting from the flow of electric charge. Lightning, batteries and even electric eels are examples of electrical energy.People use electricity for lighting, heating, cooling, and refrigeration and for operating appliances, computers, electronics, machinery, and public transportation systems.
Hope it helped you.
Answer: The chemical formula for the compound of these two elements is 
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here metal lead is having an oxidation state of +4 called as 
cation and sulphur non metal has oxidation state of -2 called as 
. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral
The chemical formula for the compound of these two elements is
Either no forces or a balanced group of forces
(not a group of "balanced forces"; there's no such thing)
The answer is d. Vacuum
Sound waves need a molecul to travel through. Gas , solid, annd liquid provide that medium.
But vacuum is just an empty space withour any moleculs in it.
Thats why in space, no one can hear you scream. Because it simply not physicsly possible
