By Laila Kearney NEW YORK (Reuters) -Oil dropped by about 2% on Friday, logging a second weekly decline, due to concern about weakened demand in China and further increases to U.S. interest rates. Brent crude settled at $87.62 a barrel, falling $2.16, or 2.4%. U.S. West Texas Intermediate (WTI) crude settled at $80.08 a barrel, losing $1.56, or 1.9%. Both benchmarks posted weekly losses, with Brent down about 9% and WTI roughly 10%. A stronger U.S. dollar, which makes oil more expensive to non-American buyers, pushed down crude prices. The market structure of both oil benchmarks shifted in way…