Answer : The final temperature of the copper is, 
Solution :
Formula used :

where,
Q = heat gained = 299 cal
m = mass of copper = 52 g
c = specific heat of copper =
= final temperature = ?
= initial temperature = 
Now put all the given values in the above formula, we get the final temperature of copper.


Therefore, the final temperature of the copper is, 
Explanation:
The magnet uses electromagnetic induction meaning it can be readily magnetized and demagnetized (using electricity) when required. When electricity is switched on, it becomes magnetized and lifts an object and when electricity is switched off, it loses magnetism and releases the object.
The magnetic is able to lift heavy objects because it has powerful conductor material (ferromagnetic iron) and the number of electromagnetic coils is many to induce a powerful magnetic force. The electric current, inducing the magnetism, is also powerful.
Learn More:
For more on electromagnetic induction check out;
brainly.com/question/3414535
brainly.com/question/13369951
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The formula we use would be the graham's law. We do as follows:
<span>E_Kr / E_Ne = sqrt ( M_Ne / M_Kr)
</span>
<span>= sqrt ( 20.1797 g/mol / 83.798 g/mol ) </span>
<span>= sqrt (0.24081) </span>
<span>= 0.4907
</span>
Hope this answers the question. Have a nice day.
It would be mol/dm^3
Formula of concentration: (no. of moles/volume of solution in dm^3)
1 cm^3 = 0.001dm^3
Hope this helped. :)