Plaintiff was engaged by defendant to act in a musical motion picture entitled Bloomer Girl; her compensation was to be $750,000. Prior to production, defendant notified plaintiff that Bloomer Girl had been canceled. She was offered a role in a western, to be titled Big Country, at the same compensation. Must plaintiff accept the new role? Why or why not? McKibben, owner of a mining claim near Fairbanks, Alaska, signed a mining lease agreement with Mohawk Oil that provided that McKibben would receive 45 per cent of the value of all ores and minerals mined. When the ore mined had a specified low value, however, McKibben would receive only 10 percent of the value of the ore mined. McKibben discovered that Mohawk Oil was diluting the ore and removing precious metals without reporting this to McKibben as required by the 7.