1. **State the problem:** We need to calculate the energy required to increase the temperature of 1.2 kg of water by 80°C. 2. **Formula:** The change in thermal energy is given by: $$\text{Energy} = m \times c \times \Delta T$$ where $m$ is the mass, $c$ is the specific heat capacity, and $\Delta T$ is the change in temperature. 3. **Given values:** - Mass, $m = 1.2$ kg - Specific heat capacity, $c = 4200$ J/kg°C - Temperature change, $\Delta T = 80$ °C 4. **Substitute the values:** $$\text{Energy} = 1.2 \times 4200 \times 80$$ 5. **Calculate step-by-step:** $$1.2 \times 4200 = 5040$$ $$5040 \times 80 = 403200$$ 6. **Final answer:** The energy needed is $$403200$$ joules.