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.
The inner core is solid, fourth layer and made out of iron and nickel. It's the one mostly in charge for the other layers. If the inner core stopped spinning, the outer core would lose its magnetic field, and this will be bad because of the sun's radiation wave. Including the other layers.
The outer core is the liquid, third layer. It's in charge of Earth's magnetic field.
The mantle is the second layer of earth, the original temperature can come up about to 1000+ or more, celsius.
The blank space in the task statement should be filled with 25 as methane can retain 25 times more heat than carbon dioxide.
<h3>Heat Retention: Methane and Carbon dioxide</h3>
Methane, carbon dioxide amongst other gases are important greenhouse gases which allows the Earth retain it's heat in order for it to be habitable.
Methane can retain and release about 25 times more heat than Carbon Dioxide although Methane emissions are lower compared to Carbon Dioxide.
Read more on Greenhouse Gases:
brainly.com/question/1878123
ΔHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
Bond enthalpies,
N ≡ N ⇒ 945 kJ mol⁻¹
N - Cl ⇒ 192 kJ mol⁻¹
Cl - Cl⇒ 242 kJ mol⁻¹
According to the balanced equation,
ΣδΗ(bond breaking) = N ≡ N x 1 + Cl - Cl x 3
= 945 + 3(242)
= 1671 kJ mol⁻¹
ΣδΗ(bond making) = N - Cl x 3 x 2
= 192 x 6
= 1152 kJ mol⁻¹
δHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
= 1671 kJ mol⁻¹ - 1152 kJ mol⁻¹
= 519 kJ mol⁻¹