A group of high altitude drones (60 000 feet) are flying over agricultural land, and spraying a mixture of various biological agents. Said drones are mainly designed to be fast (near mach speed), have a remaining range of 300 km, and would probably rely on nozzles on the body rather than have a proper boom to deploy from. The drone will be travelling in a straight line.
My question is very simple how big an area could conceivably be covered by each drone? Assuming regular wind patterns nothing funny going on here. Any help would be greatly appreciated.