1. During zone melting process, the molten zone of a Cu-Ni alloy bar has the initial composition marked by point “B" in the phase diagram. Referring to the right hand sidedrawing, the power of the heater (induction coil) was on when it travels from left end to right end so that zone melting happened. The power was off when the heater translated fully back to the left side to keep the entire bar in solid state. The heater passed the bar from left to right four times, what is the wt% of Ni at the left end of the bar.

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