Answer:
448 J/kg/°C
Explanation:
m₁ C₁ (T₁ − T) + m₂ C₂ (T₂ − T) = 0
(0.0414 kg) C (243°C − 20.4°C) + (0.411 kg) (4186 J/kg/°C) (18°C − 20.4°C) = 0
(9.22 kg°C) C − 4129 J = 0
C = 448 J/kg/°C
 
        
             
        
        
        
<span>its kinetic energy is 7350kJ 
</span>
Kinetic energy is given as = 

Now, m = 12 gms = 0.012 kg
 And, velocity = 35 kilometers/second = 35000 m/sec
Kinetic energy is given as = 
![\frac{1}{2} 0.012 kg * 35000*35000 m/[tex] s^{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B2%7D%200.012%20kg%20%2A%2035000%2A35000%20m%2F%5Btex%5D%20s%5E%7B2%7D%20)
                        = 6 

×1225 ×

 m/
 
                         = 7350 kJ
 
        
        
        
Answer:
When Helium is identified by astronomers is one of the great triumphs of spectroscopy.
Explanation:
Janssen managed to do this great triumphs on August 18, 1868 . Janssen was the first person to introduce the helium, an element that never seen before on Earth, in the solar spectrum. At that time, he didn’t know that what he’d seen—he just think that it was something new. In the mid of 1800, the spectroscope instrument is introduced in astronomy.
Later on we heard that all helium in Universe has been created by the fusion of hydrogen nuclei.
To know more about Spectroscopy:
brainly.com/question/14677550
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