Final answer:
The question regarding the solidus temperature of a copper-nickel alloy lacks the necessary phase diagram or a relationship between composition and solidus temperature to provide a correct answer.
Step-by-step explanation:
The question asks how many kilograms of nickel must be added to 4.32 kg of copper to make an alloy with a solidus temperature of 1300°C. However, it seems there is not enough context or relevant data provided in the question or additional reference information to establish a direct relationship between the mass of nickel added and the solidus temperature of the resulting copper-nickel alloy. Normally, to solve such a problem, we would need a phase diagram for the copper-nickel system that shows the solidus temperatures for various compositions. The solidus temperature is where the alloy begins to melt, and it varies with the concentration of the components in the alloy. Without the specific phase diagram or empirical formula relating the solidus temperature to the composition of a copper-nickel alloy, we cannot accurately determine the amount of nickel required.