Given :
Mass =5kg
T 
1
 
 =20 
∘
 C,T 
2
 
 =100 
∘
 C
ΔT=100−20=80 
∘
 C
Q=m×C×ΔT
where C= specific heat capacity of water 
=4200J/(kgK)
Q=5×4200×80
=1680000 Joule.
=1680KJ
 
        
             
        
        
        
 Answer: 
Explanation:
Well, lets say you park your car on the top of a hill, gravitational energy prevents it from the car falling back. Or a snow pack, aka before a potential avalanche. Though gravity cannot keep it safe forever, gravitational energy keeps it from crashing asap. In this case, it gives you time to escape. Altogether, gravitational force keeps the earth in it's atmosphere.
 
        
             
        
        
        
Answer:
(d) they are transmitted using digital signals
Explanation:
i just did the quiz an got it right
 
        
                    
             
        
        
        
Answer:
You can create an electromagnet by wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current."
Explanation:
Electromagnets are made by wrapping an insulated wire around a metal with ferromagnetic properties (example is iron), to form a loop, and then applying a current through the wire. Electromagnets can generate magnetism with a strong force field, and unlike normal magnets, their strength can be varied by varying the amount of current flowing through the coil. Their main disadvantage, which is also their most utilized property is that their magnetism is lost once the current flowing through the wire is cut-off.