Let's see.. 
- Melting
-Evaporation.
Two.
        
             
        
        
        
Answer:
Time constant of RC circuit is 0.105 seconds.
Explanation:
It is given that,
Resistance, 
Capacitance, 
We need to find the expected time constant for this RC circuit. It can be calculated as :



So, the time constant for this RC circuit is 0.105 seconds. Hence, this is the required solution.
 
        
             
        
        
        
One well-known application of density is determining whether or not an object will float on water. If the object's density is less than the density of water, it will float; if its density is less than that of water, it will sink.In fact, submarines dive below the surface of the water by emptying their ballast tanks
 
        
             
        
        
        
1 and A
2 and B
3 and D
4 and C