Hello please could you help me with the physics ?

In order to calculate the amount of energy needed, we can use the formula below:
[tex]Q=m\cdot c\cdot\Delta T[/tex]Where Q is the amount of energy in Joules, m is the mass in kg, c is the specific heat coefficient and DeltaT is the change in temperature.
So, for m = 0.8, c = 4.2*10^3 and DeltaT = 85 (from 15°C to 100°C), we have:
[tex]\begin{gathered} Q=0.8\cdot4.2\cdot10^3\cdot85 \\ Q=285600\text{ J} \end{gathered}[/tex]Then, for the energy needed to evaporate the water, we have a similar formula:
[tex]Q=m\cdot L[/tex]Where L is the latent heat. So, for L = 2.3 * 10^6, we have:
[tex]\begin{gathered} Q=0.8\cdot2.3\cdot10^6 \\ Q=1840000\text{ J} \end{gathered}[/tex]