Context: BeiDou-1 is an experimental regional navigation system, which consists of four satellites (three working satellites and one backup satellite). The satellites themselves were based on the Chinese DFH-3 geostationary communications satellite and had a launch weight of 1,000 kilograms (2,200 pounds) each.

Question: What is the BeiDou-1?
Answer: an experimental regional navigation system

Question: The BeiDou-1 is made up of how may satellites?
Answer: four

Question: How many satellites in the BeiDou-1 system is used for back up?
Answer: one

Question: What were the BeiDou-1 system satellites based on?
Answer: the Chinese DFH-3 geostationary communications satellite

Question: How much did each satellite for the BeiDou-1 system weigh?
Answer: 1,000 kilograms (2,200 pounds) each

Question: Which navigational system is regional and consists of five satellites? 
Answer: Unanswerable

Question: The launch weight of what was over 3,000 pounds? 
Answer: Unanswerable

Question: BeiDou-1 consists of four working satellites and how many backups?
Answer: Unanswerable

Question: BeiDou-1 consists of four backup satellites and how many working satellites?
Answer: Unanswerable

Question: Which navigational system is national and consists of four satellites? 
Answer: Unanswerable