For flights from Singapore to Lanzhou Zhongchuan International Airport in Gansu, China, carry-on baggage should ideally be within the size limits specified by your airline (check your booking for specifics). Generally, this means a small bag that fits under the seat in front of you. Liquids must be in containers of 100ml or less, and all containers must fit inside a single, transparent, resealable plastic bag. As for food, restrictions vary depending on the airline and whether you're bringing it from Singapore or purchasing it at the airport. It's best to check your airline's website for their specific guidelines.