Oil prices fell about 2% to a six-week low on Tuesday on rising expectations of a ceasefire in Gaza and growing demand concerns in China. Brent futures fell $1.38, or 1.7%, to $81.02 a barrel by 12:13 p.m. EST (1613 GMT), while U.S. West Texas Intermediate (WTI) crude fell $1.49, or 1.9%, to...