I'm new to drag racing and want to understand the basics. Please navigate to the 'NHRA 101' section. From there, find out what the 'Christmas Tree' is and how it works, including the difference between a 'Pro Tree' and a 'Sportsman Tree'. Additionally, tell me what the primary distinguishing feature of a Top Fuel Dragster is, based on the 'Drag Racing Classes' information.
Navigate to 'nhra.com'. Click on the 'More Menu' link (ID 92). Click on the 'NHRA 101' link (ID 112). Locate and read the description of the 'Christmas Tree' and its operation. Identify the differences between a 'Pro Tree' and a 'Sportsman Tree'. Click on the 'Drag Racing Classes' link (ID 476) within the 'NHRA 101' section. Locate the description for 'Top Fuel Dragster' and identify its primary distinguishing feature. Synthesize all gathered information into a concise answer.
The agent successfully navigates to the 'NHRA 101' page. The agent accurately describes the 'Christmas Tree' as an electronic device with lights (pre-stage, stage, amber, green, red) used to start a race, connected to trackside photocells and timers. The agent correctly differentiates between a 'Pro Tree' (all three amber lights flash simultaneously, followed four-tenths of a second later by green) and a 'Sportsman Tree' (three amber bulbs flash consecutively five-tenths of a second apart, followed five-tenths later by green). The agent successfully navigates to the 'Drag Racing Classes' page. The agent states that the primary distinguishing feature of a Top Fuel Dragster is its use of nitromethane fuel, which produces visible flames from the exhaust.