Apple Inc AAPL.O, Meta Platforms META.O and Tesla Inc TSLA.O were down 0.2% in premarket trading. By Ankika Biswas and Sruthi Shankar Sept 15 (Reuters) - Wall Street's main indexes were set for a mixed open on Thursday as a slew of economic data pointed to resilience in the U.S. economy, likely keeping the Federal Reserve on track for aggressive interest rate hikes to tame inflation. U.S. retail sales unexpectedly rose 0.3% in August as lower gasoline prices supported spending, data showed, in a sign that the economy could tolerate higher interest rates as the Fed tightens monetary policy.