By Shreyashi Sanyal Nov 9 (Reuters) - U.S. stock indexes were set to open mixed on Tuesday after data showed a solid rise in producer prices last month, while General Electric surged on its plan to split into three public companies. Accelerating inflation and tighter monetary policy have become a bigger concern for investors than the COVID-19 pandemic. It's not growing as quick as it was once feared, but it's still on the rise," said Robert Pavlik, senior portfolio manager at Dakota Wealth in Fairfield, Connecticut.