The answer has to depend on the mass of the copper that you're trying to melt.
But there is a formula which you can calculate the energy required if you have the information of the mass. This formula requires the value called specific latent heat of fusion, which is the energy required to melt or freeze a specific mass of copper without changing its temperature but change its state.

E is the total energy required, m is the mass, and lv is the specific latent heat of fusion of copper.
Usually, in questions, lv is given. But we can also look it up online which is around 205kJ kg^-1
this means, to melt or freeze a copper, we need to work the mass multiplied by 205kJ in order to calculate its total energy needed or released.
<span>1.) a. 20 ÷ 4 ? means ? × 4 = 20 </span>→ replace ? with 5.<span>
b. 2,725 ÷ 5 ? means ? × 5 = 2,725 </span>→ replace ? with 545<span>
c. ? ÷ 5 = 0 </span>→ replace ? with 0.
2) 1,475 / 25 = 59
They used 59 boxes for this year.
3) 18 per haircut ; 70 per perm
4,608 = 18h + 70(36)
4,608 - 2,520 = 18h
2,088 = 18h
2,088/18 = h
116 = h
Grace did 116 haircuts.
4) 575 + 13(118) = 575 + 1,534 = 2,109 total expense.
5) 2,240 miles / 320 miles = 7 tanks of gas used.
7 tanks * 39 = 273 cost of the gas used.
Answer:
LOL i belive its 200 because i did this exact same thing yesterday for homework and got it right so yeah, it should work. if it doesnt im sorry! but yeah XD sub to my yt channel too! DB_PLAYS <3
Explanation: