(Reuters) - Apple Inc (AAPL.O) Chief Executive Tim Cook, whose products were spared from new U.S. tariffs on Chinese goods imposed on Monday, said he is optimistic that the United States and China will eventually work through their trade differences. “I’m optimistic because trade is one of those things where it’s not a zero-sum game,” Cook told ABC News’ “Good Morning America” program on Tuesday. “I’m optimistic that the two countries will sort this out and life will go on.”